Gilera Nexus 125 i.e. MY 2008 (EN)

SERVICE STATION MANUALxxxxxx IT - xxxxxx EN - xxxxxx FR - xxxxxx DE -xxxxxx ES - xxxxxx PT - xxxxxx NL - xxxxxx EL

MSS Nexus 125 i.e. (2008)

SERVICE STATIONMANUAL

MSS Nexus 125 i.e. (2008)

The descriptions and illustrations given in this publication are not binding. While the basic specificationsas described and illustrated in this manual remain unchanged, PIAGGIO-GILERA reserves the right, at

any time and without being required to update this publication beforehand, to make any changes tocomponents, parts or accessories, which it considers necessary to improve the product or which are

required for manufacturing or construction reasons.Not all versions/models shown in this publication are available in all countries. The availability of each

model should be checked at the official Piaggio sales network."© Copyright 2008 - PIAGGIO & C. S.p.A. Pontedera. All rights reserved. Reproduction of this publication

in whole or in part is prohibited."PIAGGIO & C. S.p.A. - Aftersales

V.le Rinaldo Piaggio, 23 - 56025 PONTEDERA (Pi)

SERVICE STATION MANUALMSS Nexus 125 i.e. (2008)

This service station manual has been drawn up by Piaggio & C. SpA to be used by the workshops ofPiaggio-Gilera dealers. It is assumed that the user of this manual for maintaining and repairing Piaggiovehicles has a basic knowledge of mechanical principles and vehicle repair technique procedures. Anysignificant change to vehicle characteristics or to specific repair operations will be communicated byupdates to this manual. Nevertheless, no mounting work can be satisfactory if the necessary equipmentand tools are unavailable. It is therefore advisable to read the sections of this manual concerning specialtools, along with the special tool catalogue.

N.B. Provides key information to make the procedure easier to understand and carry out.

CAUTION Refers to specific procedures to carry out for preventing damages to the vehicle.

WARNING Refers to specific procedures to carry out to prevent injuries to the repairer.

Personal safety Failure to completely observe these instructions will result in serious risk of personalinjury.

Safeguarding the environment Sections marked with this symbol indicate the correct use of the vehicleto prevent damaging the environment.

Vehicle intactness The incomplete or non-observance of these regulations leads to the risk of seriousdamage to the vehicle and sometimes even the invalidity of the guarantee.

INDEX OF TOPICS

CHARACTERISTICS CHAR

TOOLING TOOL

MAINTENANCE MAIN

TROUBLESHOOTING TROUBL

ELECTRICAL SYSTEM ELE SYS

ENGINE FROM VEHICLE ENG VE

ENGINE ENG

INJECTION INJEC

SUSPENSIONS SUSP

BRAKING SYSTEM BRAK SYS

COOLING SYSTEM COOL SYS

CHASSIS CHAS

PRE-DELIVERY PRE DE

TIME TIME

INDEX OF TOPICS

CHARACTERISTICS CHAR

This section describes the general specifications of the vehicle.

Rules

This section describes general safety rules for any maintenance operations performed on the vehicle.

Safety rules

- If work can only be done on the vehicle with the engine running, make sure that the premises are well

ventilated, using special extractors if necessary; never let the engine run in an enclosed area. Exhaust

fumes are toxic.

- The battery electrolyte contains sulphuric acid. Protect your eyes, clothes and skin. Sulphuric acid is

highly corrosive; in the event of contact with your eyes or skin, rinse thoroughly with abundant water

and seek immediate medical attention.

- The battery produces hydrogen, a gas that can be highly explosive. Do not smoke and avoid sparks

or flames near the battery, especially when charging it.

- Fuel is highly flammable and it can be explosive given some conditions. Do not smoke in the working

area, and avoid naked flames or sparks.

- Clean the brake pads in a well-ventilated area, directing the jet of compressed air in such a way that

you do not breathe in the dust produced by the wear of the friction material. Even though the latter

contains no asbestos, inhaling dust is harmful.

Maintenance rules

- Use original PIAGGIO spare parts and lubricants recommended by the Manufacturer. Non-original or

non-conforming spares may damage the vehicle.

- Use only the appropriate tools designed for this vehicle.

- Always use new gaskets, sealing rings and split pins upon refitting.

- After removal, clean the components using non-flammable or low flash-point solvents. Lubricate all

the work surfaces, except tapered couplings, before refitting these parts.

- After refitting, make sure that all the components have been installed correctly and work properly.

- For removal, overhaul and refit operations use only tools with metric measures. Metric bolts, nuts and

screws are not interchangeable with coupling members with English measurement. Using unsuitable

coupling members and tools may damage the vehicle.

- When carrying out maintenance operations on the vehicle that involve the electrical system, make

sure the electrical connections have been made properly, particularly the ground and battery connec-

tions.

MSS Nexus 125 i.e. (2008) Characteristics

CHAR - 7

Vehicle identification

To read the chassis prefix, lift the saddle and re-

move the lid «A».

The engine prefix «B» is stamped near the rear left

shock absorber lower support.

VEHICLE IDENTIFICATIONSpecification Desc./QuantityChassis prefix M35700

ENGINE PREFIX M357M

Characteristics MSS Nexus 125 i.e. (2008)

CHAR - 8

Dimensions and mass

WEIGHTS AND DIMENSIONSSpecification Desc./QuantityKerb weight 169 ± 5 kg

Maximum weight allowed 370 KgMaximum height 1.400 mm

Width 780 mmWheelbase 1.515 mm

Maximum length 2,110 mm

Engine

ENGINESpecification Desc./Quantity

Type Single-cylinder, 4-stroke with double spark plugEngine capacity 124 cm³

Bore x stroke 57.0 x 48.6 mmCompression ratio 11.5 ± 13.0: 1Engine idle speed 1,750 ± 50 rpmValve clearance Intake: 0.10 mm Exhaust: 0.15 mm

Max. power 11.0 kW at 9,500 rpmMAX. torque 12.0 Nm at 8000 rpmLubrication With lobe pump (inside crankcase) controlled by a chain with

double filter: mesh and paperLubrication pressure 3 ÷ 4 bar

Minimum lubrication pressure (90° C) 0.6 ÷ 1.2 bar


CHAR - 9

Specification Desc./QuantityFuel system 32 MIU2.E0 Electronic injection with Ø 32-mm throttle body and

electric fuel pump.Cooling Forced-circulation coolant with electric pump commanded by

the control unit.Fuel Unleaded petrol (95 RON)

Transmission

TRANSMISSIONSpecification Desc./QuantityTransmission CVT expandable pulley variator with torque server, V-belt, self-

ventilating dry automatic centrifugal clutch and transmissionhousing with forced-circulation air cooling.

Final reduction gear Gear reduction unit in oil bath.

Capacities

CAPACITYSpecification Desc./Quantity

Engine oil 1.30 lTransmission oil 250 cm³

Cooling system fluid 1.75 lFuel tank (reserve) approx.15.00 l (approx. 2.80 l)

Electrical system

ELECTRICAL SYSTEMSpecification Desc./Quantity

Electric starterIgnition Electronic inductive discharge ignition, high efficiency, with

separate HV coil.Ignition advance α/N three-dimensional map managed by control unit

Spark plug NGK CR8EKBBattery Sealed, 12 V / 12 Ah

Generator alternating current

Frame and suspensions

CHASSIS AND SUSPENSIONSSpecification Desc./Quantity

Chassis Tubular and steel sheets.Front suspension Hydraulic telescopic fork with Ø 35-mm stem

Front suspension travel 104 mmRear suspension Two double-acting shock absorbers with preloading adjust-

ment in 4 positions.Rear suspension travel 95.5 mm


CHAR - 10

Brakes

BRAKESSpecification Desc./QuantityFront brake Ø 260-mm disc brake with hydraulic control activated by han-

dlebar right-side lever.Rear brake Ø 240 mm disc brake with hydraulic control activated by han-

dlebar left lever.

Wheels and tyres

WHEELS AND TYRESSpecification Desc./QuantityWheel rim type Light alloy wheel rims.

Front rim 15'' x 3.00Rear rim 14'' x 3.50Front tyre Tubeless, 120/70 - 15'' 56PRear tyre Tubeless 140/70 - 14'' 64P

Front tyre pressure (with passenger) 2.1 bar (-)Rear tyre pressure (with passenger) 2.4 bar (-)

N.B.

CHECK AND ADJUST TYRE PRESSURE WITH TYRES AT AMBIENT TEMPERATURE. REGU-LATE PRESSURE ACCORDING TO THE WEIGHT OF BOTH RIDER AND ACCESSORIES

Tightening Torques

STEERINGName Torque in Nm

Steering upper ring nut 30 ÷ 33Steering lower ring nut 10 ÷ 13 then loosen by 90°Handlebar fixing screw 50 to 55

Fixing screws for the handlebar control unit U-bolts 7 to 10

STEERING (VERSION WITH FIFTH WHEEL)Name Torque in Nm

Steering upper ring nut 40 ÷ 45Steering lower ring nut 10 ÷ 12

CHASSISName Torque in Nm

Centre stand bolt 25 ÷ 30Side stand bolt (°) 35 ÷ 40

Engine-swinging arm pin 55 ÷ 61Frame-swinging arm bolt 55 ÷ 61

Engine arm bolt - frame arm 40 ÷ 45(°) Apply LOCTITE 243 medium-strength threadlock

FRONT SUSPENSIONName Torque in Nm

Fork leg screw 6 - 7Front wheel axle 45 to 50Fork plate screw 25 ÷ 34

REAR SUSPENSIONName Torque in Nm

Shock absorber upper clamp 33 to 41


CHAR - 11

Name Torque in NmShock absorber lower clamping 33 to 41

Rear wheel axle 104 to 126Shock absorber-crankcase attachment bracket 20 ÷ 25

Muffler arm clamping screws 27 ÷ 30

FRONT BRAKEName Torque in Nm

Oil bleed screw 8 - 12Disc tightening screw (°) 5 to 6

Brake fluid tube-calliper fitting 16 - 20Brake fluid pump-hose fitting 16 - 20

Tightening screw for calliper support to the fork 45 ÷ 55

REAR BRAKEName Torque in Nm

Rear brake disc screws(°) 5 ÷ 6.5Rear brake calliper-pipe fitting 20 to 25

Rigid / flexible pipe fitting 13 ÷ 18Rear brake pump-pipe fitting 16 ÷ 20

Rear brake calliper fixing screws 20 ÷ 25

REAR BRAKEProduct Description Specifications

(°) Loctite 243 Medium strength threadlock Apply LOCTITE 243 medium-strengththreadlock

SILENCERName Torque in Nm

Silencer heat guard fixing screw 4 to 5Screw for fixing silencer to supporting arm 20 to 25

Lambda probe tightening on exhaust manifold 40 to 50Exhaust manifold-silencer joint tightening 12÷13

Manifold - silencer diaphragm tightening clamp 16 to 18

LUBRICATIONName Torque in Nm

Hub oil drainage plug 15 to 17Oil filter on crankcase fitting 27 to 33

Engine oil drainage plug/ mesh filter 24 to 30Oil filter 4 to 6

Oil pump cover screws 7 - 9Screws fixing oil pump to the crankcase 5 to 6

Oil pump command sprocket screw 10 to 14Oil pump cover plate screws 4 to 6

Oil sump screws 10 to 14Minimum oil pressure sensor 12 to 14

CYLINDER HEADName Torque in Nm

Spark plug 12 to 14Head cover screws 6 - 7

Nuts fixing head to cylinder 7±1 + 10±1 + 270°Head fixing side screws 11 ÷ 12

Starter ground screw 7 to 8.5Tappet adjustment check nut 6 - 8

Intake manifold screws 11 to 13Timing chain tensioner slider screw 10 to 14Starter counterweight support screw 11 to 15Timing chain tensioner support screw 11 to 13Timing chain tensioner central screw 5 to 6

Camshaft retention plate screw 4 to 6


CHAR - 12

TRANSMISSIONName Torque in Nm

Belt support roller screw 11 to 13Clutch unit nut on driven pulley 45 to 50

Drive pulley nut 75 - 83Transmission cover screws 11 to 13

Driven pulley shaft nut 54 ÷ 60Rear hub cap screws 24 to 27

FLYWHEELName Torque in Nm

Flywheel cover screw 11 to 13Stator assembly screws 3 - 4 (Apply LOCTITE medium type 242 threadlock)

Flywheel nut 94 ÷ 102Pick-up fixing screws 3 to 4

Screw fixing freewheel to flywheel 13 - 15

CRANKCASE AND CRANKSHAFTName Torque in Nm

Internal engine crankcase bulkhead (transmission-side halfshaft) screws

4 to 6

Engine-crankcase coupling screws 11 to 13Starter screws 11 to 13

Crankcase timing cover screws 3.5 - 4.5 (Apply LOCTITE medium type 242 threadlock)

COOLINGName Torque in Nm

Water pump rotor cover 3 to 4Thermostat cover screws 3 to 4

Bleed screw 3

Overhaul data

Assembly clearances


CHAR - 13

Cylinder - piston assy.

ENGINE COUPLING CATEGORIESName Initials Cylinder Piston Play on fitting

Cylinder A 56.997 to 57.004 56.945 - 56.952 0.045 - 0.059Cylinder B 57.004 to 57.011 56.952 - 56.959 0.045 - 0.059Piston C 57.011 to 57.018 56.959 - 56.966 0.045 - 0.059Piston D 57.018 to 57.025 56.966 - 56.973 0.045 - 0.059

Cylinder 1st Oversize A1 57.197 to 57.204 57.145 - 57.152 0.045 - 0.059Cylinder 1st Oversize B 1 57.204 to 57.211 57.152 - 57.159 0.045 - 0.059Piston 1st Oversize C 1 57.211 to 57.218 57.159 - 57.166 0.045 - 0.059Piston 1st Oversize D 1 57.218 to 57.225 57.166 - 57.173 0.045 - 0.059

Cylinder 2nd Oversize A2 57.397 to 57.404 57.345 - 57.352 0.045 - 0.059Cylinder 2nd Oversize B 2 57.404 to 57.411 57.352 - 57.359 0.045 - 0.059Piston 2nd Oversize C 2 57.411 to 57.418 57.359 - 57.366 0.045 - 0.059Piston 2nd Oversize D 2 57.418 to 57.425 57.366 - 57.373 0.045 - 0.059

Cylinder 3rd Oversize A 3 57.597 to 57.604 57.545 - 57.552 0.045 - 0.059Cylinder 3rd Oversize B 3 57.604 to 57.611 57.552 - 57.559 0.045 - 0.059Piston 3rd Oversize C 3 57.611 to 57.618 57.559 - 57.566 0.045 - 0.059Piston 3rd Oversize D 3 57.618 to 57.625 57.566 - 57.573 0.045 - 0.059

N.B.

THE PISTON MUST BE INSTALLED WITH THE ARROW FACING TOWARDS THE EXHAUST SIDE,THE PISTON RINGS MUST BE INSTALLED WITH THE WORD «TOP» OR THE STAMPED MARKFACING UPWARDS.


CHAR - 14

- Calculate the coupling clearance between pin

and connecting rod small end.

CharacteristicStandard diameter:Ø 14.996 - 15.0 mm

Standard clearance:0.015 - 0.029 mm

- Measure the diameter of the bearings on the pis-

ton.

CharacteristicStandard diameter:15 +0.006 + 0.001mm

- Calculate the piston pin coupling clearance.N.B.

THE PIN HOUSINGS HAVE 2 LUBRICATION CHANNELS. FOR THIS REASON, MEASUREMENTMUST BE MADE ACCORDING TO THE PISTON AXIS.

CharacteristicStandard clearance:

0.001 - 0.010 mm

- Check that coating is free from flakes.

- Check that the head matching surface exhibits no

deformations or wear.

CharacteristicMaximum allowable run-out:0.05 mm

- Pistons and cylinders are classified into categories based on their diameter. The coupling is carried

out in pairs (A-A, B-B, C-C, D-D).


CHAR - 15

*Fit rings «2» and «3» with the word «TOP» facing upwards.

** Position the port of the rings as shown here.

*** Value «A» of the sealing ring inside the cylinder (fitting clearance).

Check the size of the sealing ring opening:

Compression ring 0.15 - 0.30 mm. Max. value 0.5 mm

Oil scraper ring 0.10 - 0.30 mm. Max. value 0.65 mm

Oil scraper ring 0.15 - 0.35 mm. Max. value 0.65 mmN.B.

FITTING CLEARANCE VALUES ARE THE SAME FOR BOTH THE STANDARD SEALING RINGSAND THE OVERSIZES.

Crankcase - crankshaft - connecting rod

- Measure the diameter of bushings «A» in the

three directions shown in the figure.

- Measure the diameter of the crankshaft bearings

«B».

- Check that the diametral clearance «A-B» is be-

tween the pre-set interval.

CharacteristicDiameter clearance0.023 - 0.041 mm


CHAR - 16

If value «A-B» is above the limit, check that value «B» is within the admissible values of the categories.

CRANKSHAFTSpecification Desc./Quantity

Category 1 28.998 to 29.004Category 2 29.004 to 29.010

If the crankshaft is within the set limits, replace the crankshaft half-bearings mounting the crankcase

so as to suit the specified couplings. The crankcase halves can be mounted with four types of crankshaft

half-bearings identified by letters- B (blue), C (yellow), E (green).

CRANKCASESpecification Desc./Quantity

Category 1 32.959 - 35.965Category 2 32.953 to 32.959

CRANKCASE - CRANKSHAFT COUPLING / CRANKSHAFT HALF-BEARINGSSpecification Desc./Quantity

Crankshaft category 1 - Crankcase category 1 E+ECrankshaft category 2 - Crankcase category 1 C+CCrankshaft category 1 - Crankcase category 2 C+CCrankshaft category 2 - Crankcase category 2 B+B

CharacteristicAxial crankshaft/crankcase clearance:

0.5 - 0.40 mm


CHAR - 17

CRANKSHAFT/ CRANKCASE AXIAL CLEARANCEName Description Dimensions Initials Quantity

Transmissionside half-shaft

16.6 +0-0.05 A D = 0.20 ÷ 0.50

Flywheel-side halfshaft 16.6 +0-0.05 B D = 0.20 ÷ 0.50Connecting rod 18 -0.10 -0.15 C D = 0.20 ÷ 0.50

Spacer tool 51.4 +0.05 E D = 0.20 ÷ 0.50

THE CRANKSHAFT is available in two CATEGO-

RIES:

CharacteristicCrankshaft category:CAT. 1 - CAT. 2

CRANKSHAFT CATEGORY IDENTIFICATION:

The identification is indicated on the counterweight shoulder «*1 - *2», if carried out with micropinholing.

Otherwise, «1 - 2» if done manually with an electric pen. The spare part identification is located on the

package with a drawing number plus FC1/FC2 or (001/002).

If a crankshaft comprising two half-shafts of different categories needs to be replaced, also replace both

crankcase halves, combining the two components (Shaft and Crankcase) featuring the same category.

Cylinder Head

Before performing head service operations, thoroughly clean all coupling surfaces. Note the position of

the springs and the valves so as not to change the original position during refitting


CHAR - 18

- Using a trued bar and a feeler gauge check that

the cylinder head surface is not worn or distorted.

CharacteristicMaximum allowable run-out0.09 mm

- In case of faults, replace the head.

- Check the sealing surfaces for the intake and exhaust manifold.

- Check that the camshaft and the rocking lever pin capacities exhibit no wear.

- Check that the head cover surface is not worn.

- Check that the coolant seal plug exhibits no oxidation.

- Insert the valves into the cylinder head.

- Alternatively check the intake and exhaust

valves.

- The test is carried out by filling the manifold with

petrol and checking that the head does not ooze

through the valves when these are just pressed

with the fingers.

Measure the camshaft bearing seats and rocking

lever support pins with a bore meter

HEAD BEARINGSSpecification Desc./Quantity

Bearing "A" 37 +0.025Bearing "B" 20 +0.021Bearing "C" 12 +0.018


CHAR - 19

- Measure the unloaded spring length.

CharacteristicStandard length40.5 mm

Allowable limit after use:39.7 mm

- Clean the valve seats of any carbon residues.

- Using the Prussian blue, check the width of the

impression on the valve seat "V".

CharacteristicAdmissible limit:1.6 mm

- If the width of the impression on the valve seat exceeds the specified limits, replace the cylinder head.

- In case of excessive wear or damage, replace the head.

STANDARD VALVE LENGTHSpecification Desc./Quantity

Intake 84.5 mmExhaust 94.5 mm

- Measure the diameter of the valve stems in the three positions indicated in the diagram.

STANDARD DIAMETERSpecification Desc./Quantity

Intake: 4.987 - 4.972 mmExhaust: 4.975 - 4.960 mm

MINIMUM ADMISSIBLE DIAMETERSpecification Desc./Quantity

Intake: 4.96 mm


CHAR - 20

Specification Desc./QuantityExhaust: 4.945 mm

- Calculate the clearance between valve and valve

guide.

- Check the deviation of the valve stem by resting

it on a «V» shaped abutment and measuring the

extent of the deformation with a dial gauge.

CharacteristicLimit values admitted:0.1 mm

- Check the concentricity of the valve head by ar-

ranging a dial gauge at right angle relative to the

valve head and rotate it on a "V" shaped abutment.

CharacteristicAdmissible limit:0.03 mm

Measure the valve guide.

CharacteristicValve guide:5 +0.012 mm


CHAR - 21

- After measuring the valve guide diameter and the

valve stem diameter, check clearance between

guide and stem.

EXHAUSTSpecification Desc./Quantity

Standard clearance: 0.025 to 0.052 mmAdmissible limit: 0.09 mm

INTAKESpecification Desc./Quantity

Standard clearance: 0.013 - 0.04 mmAdmissible limit: 0.08 mm

- Check that there are no signs of wear on the surface of contact with the articulated register terminal.

- If no faults are found during the above checks,

you can use the same valves. To obtain better

sealing performance, grind the valve seats. Grind

the valves gently with a fine-grained lapping com-

pound. During the grinding, keep the cylinder head

with the valve axes in a horizontal position. This

will prevent the lapping compound residues from

penetrating between the valve stem and the guide

(see figure).CAUTIONTO AVOID SCORING THE FAYING SURFACE, DO NOT KEEP ROTATING THE VALVE WHEN NOLAPPING COMPOUND IS LEFT. CAREFULLY WASH THE CYLINDER HEAD AND THE VALVESWITH A SUITABLE PRODUCT FOR THE TYPE OF LAPPING COMPOUND BEING USED.CAUTION


CHAR - 22

DO NOT REVERSE THE FITTING POSITIONS OF THE VALVES (RIGHT - LEFT).- Check that the camshaft bearings exhibit no scores or abnormal wear.

- Using a micrometer, measure the camshaft bearings.

STANDARD DIAMETERSpecification Desc./QuantityBearing A Ø: 37 - 0.025 -0.050 mm

Bearing B diameter: 19 - 0.020 -0.041 mm

MINIMUM ADMISSIBLE DIAMETERSpecification Desc./QuantityBearing A Ø: 36.940 mm

Bearing B diameter: 19.950 mm

-Using a gauge, measure the cam height.

STANDARD HEIGHTSpecification Desc./Quantity

intake 17.382 mmExhaust 16.563 mm

ADMISSIBLE LIMITSSpecification Desc./Quantity

intake 17.130 mmExhaust 16.310 mm

standard axial clearance 0.11 - 0.41 mmmaximum admissible axial clearance 0.42 mm

- Check that the rocking lever pins exhibit no scores or wear.

CharacteristicStandard diameterDiameter 11.977 - 11.985 mm


CHAR - 23

- Measure the inside diameter of each rocker.

CharacteristicStandard diameterØ 12 +0.011 mm

- Check that the cam contact sliding block and the

articulated register cap is free from wear.

- In case of wear, replace the component.

Slot packing system

CharacteristicCompression ratioCr: 11.50 - 13:1

Measurement «A» to be taken, is a value of piston protrusion. It indicates by how much the plane formed

by the piston crown protrudes from the plane formed by the upper part of the cylinder. The further the

piston protrudes from the cylinder, the thicker the base gasket to be used (to restore the compression

ratio) and vice versa.


CHAR - 24

N.B.

NO GASKETS AND SEALS SHOULD BE ASSEMBLED BETWEEN THE CRANKCASE AND CYL-INDER AND THE DIAL GAUGE EQUIPPED WITH SUPPORT SHOULD BE SET TO ZERO FORMEASUREMENT «A» TO BE TAKEN WITH THE PISTON AT TOP DEAD CENTRE POSITION ANDON A RECTIFIED PLANE.

MODELS WITH METAL HEAD GASKET (0.3)Name Measure A Thickness

Shimming 125 - Cylinder 67.8 - Headgasket 0.3 - Base gasket 0.6

1.40 - 1.60 0.60 ± 0.05

Shimming 125 - Cylinder 67.8 - Headgasket 0.3 - Base gasket 0.8

1.60 - 1.80 0.80 ± 0.05

Products

RECOMMENDED PRODUCTS TABLEProduct Description Specifications

AGIP GEAR 80W-90 Oil for speed gearbox SAE 80W-90, API GL-4 mineral multi-grade oil

AGIP CITY HI TEC 4T Oil to lubricate flexible transmissions(throttle control)

Oil for 4-stroke engines

AGIP GP 330 Grease for brake levers, throttle White calcium complex soap-basedspray grease with NLGI 2; ISO-L-XBCIB2

AGIP CITY HI TEC 4T Engine oil SAE 5W-40, API SL, ACEA A3, JASO MASynthetic oil

AGIP BRAKE 4 Brake fluid FMVSS DOT 4 Synthetic fluidAGIP PERMANENT SPECIAL coolant Monoethylene glycol-based antifreeze

fluid, CUNA NC 956-16AUTOSOL METAL POLISH Silencer cleaning paste special product for cleaning and polishing

stainless steel silencerAGIP GREASE PV2 Grease for steering bearings, pin seats

and swinging armSoap-based lithium and zinc oxidegrease containing NLGI 2; ISO-L-

XBCIB2 of the swinging arm

UNIT OF MEASURE - CONVERSION - ENGLISH SYSTEM TO INTERNATIONAL SYSTEM (IS).Specification Desc./Quantity

1 Inch (in) 25.4 Millimetres (mm)1 Foot (ft) 0.305 Meter (m)1 Mile (mi) 1.609 Kilometre (km)

1 US Gallon (USgal) 3.785 Litre (l)1 Pound (lb) 0.454 Kilogram (kg)

1 Cubic inch (in³) 16.4 Cubic centimetres (cm³)1 Foot pound (ft lb) 1,356 Newton meter (Nm)

1 Mile per hour (mi/h) 1,602 Kilometres per hour (km/h)1 Pound per square inch (PSI) 0.069 (bar)

1 Fahrenheit (°F) 32+(9/5) Celsius (°C)


CHAR - 25

INDEX OF TOPICS

TOOLING TOOL

SPECIFIC TOOLSStores code Description

001330Y Tool for fitting steering seats

001467Y014 Calliper to extract ø 15-mm bearings

005095Y Engine support

002465Y Calliper for circlips

006029Y Punch for fitting fifth wheel seat on steer-ing bearing

020004Y Punch for removing steering bearingsfrom headstock

020055Y Wrench for steering tube ring nut

MSS Nexus 125 i.e. (2008) Tooling

TOOL - 27

Stores code Description020074Y Support base for checking crankshaft

alignment

020150Y Air heater mounting

020151Y Air heater

020193Y Oil pressure check gauge

020262Y Crankcase splitting plate

020263Y Driven pulley assembly sheath

Tooling MSS Nexus 125 i.e. (2008)

TOOL - 28

Stores code Description020306Y Punch for assembling valve seal rings

020329Y Mity-Vac vacuum-operated pump

020330Y Stroboscopic light to check timing

020331Y Digital multimeter

020332Y Digital rpm indicator


TOOL - 29

Stores code Description020648Y Single battery charger

020335Y Magnetic mounting for dial gauge

020357Y 32x35-mm Adaptor020359Y 42x47-mm Adaptor

020360Y 52x55-mm Adaptor

020363Y 20-mm guide


TOOL - 30

Stores code Description020375Y 28 x 30 mm adaptor

020376Y Adaptor handle

020382Y Valve cotters equipped with part 012 re-moval tool

020382Y011 adapter for valve removal tool

020393Y Piston assembly band

020412Y 15-mm guide


TOOL - 31

Stores code Description020423Y Driven pulley lock wrench

020424Y Driven pulley roller casing fitting punch

020426Y Piston fitting fork

020431Y Valve oil seal extractor

020434Y Oil pressure check fitting

020444Y Tool for fitting/ removing the driven pulleyclutch


TOOL - 32

Stores code Description020456Y Ø 24 mm adaptor020477Y 37 mm adaptor

020483Y 30-mm guide

020489Y Hub cover support stud bolt kit

020428Y Piston position check mounting

020680Y Diagnosis Tool


TOOL - 33

Stores code Description020621Y HV cable extraction adaptor

001467Y035 Bearing housing, out ø 47 mm

020626Y Driving pulley lock wrench

020626Y008 Driving pulley lock wrench001467Y013 Calliper to extract ø 15-mm bearings

020627Y Flywheel lock wrench

020467Y Flywheel extractor


TOOL - 34

Stores code Description020430Y Pin lock fitting tool

020622Y Transmission-side oil seal punch

020480Y Petrol pressure check kit

020244Y 15-mm diameter punch

020115Y Ø 18 punch

020271Y Tool for removing-fitting silent bloc


TOOL - 35

Stores code Description020469Y Reprogramming kit for scooter diagnostic

tester

001467Y017 Driver for OD 36 mm bearings

020234y extractor020441Y 26 x 28 mm adaptor

020362Y 12 mm guide

020358Y 37x40-mm Adaptor001467Y002 Driver for OD 73 mm bearing


TOOL - 36

Stores code Description020688Y Dial gauge support


TOOL - 37

INDEX OF TOPICS

MAINTENANCE MAIN

Maintenance chart

SCHEDULED MAINTENANCE TABLEI: CHECK AND CLEAN, ADJUST, LUBRICATE OR REPLACE IF NECESSARY.C: CLEAN, R: REPLACE, A: ADJUST, L: LUBRICATE* Replace every 2 years

Km x 1,000 1 5 10 15 20 25 30 35 40 45 50 55 60Roller bearing - Driven pulley L L L L L LSafety fasteners I I I I ISpark plug R R R R R RDrive belt I R I R I R I RThrottle control A A A A A A AAir filter C C C C C COil filter R R R R R R RCVT Filter C C C C C CValve clearance A A AElectrical system and battery I I I I I I IBrake levers L L L L L L LBrake fluid * I I I I I I ICoolant * I I I I I I IEngine oil R I R I R I R I R I R I RHub oil R I R I R I RHeadlight direction adjustment A A A ABrake pads I I I I I I I I I I I I ISliding shoes / CVT rollers R R R R R RTyre pressure and wear I I I I I I IVehicle road test I I I I I I IRadiator (external cleaning) I I I ISuspension I I I I I I ISteering A A A A A A ATransmission L L L L

Spark plug

Proceed as follows:

1. Lift the rubber mat;

2. Remove the right side cover unscrewing the 3

fixing «A» screws;

3. Disconnect the spark plug HV wire hood «B»;

4. Unscrew the spark plug using the wrench sup-

plied;

5. Upon refitting, place the spark plug into the hole

at the required angle and finger tighten it;

6. Use the wrench only to tighten it;

7. Push hood «B» fully over the spark plug.WARNINGTHE USE OF SPARK PLUGS OTHER THAN THOSE REC-OMMENDED OR A SHIELDLESS SPARK PLUG CAPCOULD CAUSE DISTURBANCES TO THE SYSTEM.CAUTION

MSS Nexus 125 i.e. (2008) Maintenance

MAIN - 39

THE SPARK PLUG MUST BE REMOVED WHEN THE EN-GINE IS COLD. REPLACE THE SPARK PLUG AS INDICA-TED IN THE SCHEDULED MAINTENANCE TABLE. USINGNON-COMPLYING ELECTRONIC IGNITIONS OR SPARKPLUGS OTHER THAN THOSE PRESCRIBED MAY SERI-OUSLY DAMAGE THE ENGINE.

CharacteristicSpark plugNGK CR8EB

Electric characteristicElectrode gap0.7 to 0.8 mm

Locking torques (N*m)Spark plug 12 ÷ 14

Hub oil

Check

-Park the vehicle on its centre stand on flat ground;

-Remove the oil dipstick «A», dry it with a clean

cloth. Reinsert it tightening it fully;

Remove the dipstick and check that the oil level is

slightly over the second notch starting from the

lower end; if the level is under the MAX. mark, it

needs to be filled with the right amount of hub oil.

-Screw up the oil dipstick again and make sure it

is locked properly into place.

Maintenance MSS Nexus 125 i.e. (2008)

MAIN - 40

Replacement

-Remove the oil filler cap «A».

- Unscrew the oil drainage cap «B» and drain out

all the oil.

- Screw in the drainage cap again and fill the hub

with the prescribed oil.

Recommended productsAGIP ROTRA 80W-90 Rear hub oilSAE 80W/90 Oil that exceeds the requirements of

API GL3 specifications

CharacteristicTransmission oil250 cm³

Locking torques (N*m)Hub oil drainage screw 15 to 17 Nm

Air filter

To remove them, proceed as follows:

1. Unscrew the 9 fixing screws «A»;

2. Remove the air filter «B»CAUTION

IF THE VEHICLE IS USED ON DUSTY ROADS IT IS NEC-ESSARY TO CARRY OUT MAINTENANCE CHECKS OFTHE AIR FILTER MORE OFTEN TO AVOID DAMAGING THEENGINE.

Cleaning:


MAIN - 41

• Wash the sponge «C» with water and mild soap.

• Dry it with a clean cloth and short blasts of compressed air.

• Soak it in a mixture of 50% petrol and 50% specified oil.

• Gently squeeze the filtering element, let it drip and then refit it.CAUTION

IF THE VEHICLE IS USED ON DUSTY ROADS IT IS NECESSARY TO CARRY OUT MAINTENANCECHECKS OF THE AIR FILTER MORE OFTEN TO AVOID DAMAGING THE ENGINE.

Recommended productsAGIP FILTER OIL Oil for air filter sponge

Mineral oil with specific additives for increased adhesiveness

CVT filter removal

- Unscrew the two screws «1» fixing the air filter to

the engine.

- Unscrew the three screws «2» and remove the

crankcase cover «3».


transmission housing filter cover «5».

- Take out the filtering element «6» from the cover.


MAIN - 42

CVT filter cleaning

1. Wash the sponge with water and neutral soap.

2. Dry it with a clean cloth and small blasts of com-

pressed air.CAUTION

IF THE VEHICLE IS USED ON DUSTY ROADS SERVICETHE CVT FILTER MORE OFTEN TO AVOID DAMAGINGTHE ENGINE.

Engine oil

In four stroke engines, the engine oil is used to lubricate the timing elements, the bench bearings and

the thermal group. An insufficient quantity of oil can cause serious damage to the engine.

In all four stroke engines, the deterioration of the oil characteristics, or a certain consumption should

be considered normal, especially if during the run-in period. Consumption levels in particular can be

influenced by the conditions of use (e.g.: oil consumption increases when driving at "full throttle".

Replacement

Change oil as indicated in the scheduled mainte-

nance table. The engine must be emptied by drain-

ing the oil through the drainage plug «B» of the

mesh pre-filter, flywheel side; furthermore, to fa-

cilitate oil drainage, loosen the cap/dipstick «A».

Once all the oil has drained through the drainage

opening, unscrew and remove the oil cartridge fil-

ter «C ».

Since a certain quantity of oil still remains in the

circuit, fill adding approx. 600 ÷ 650 cm³ of oil

through the cap «A». Then start up the vehicle,

leave it running for a few minutes and switch it off:

After about five minutes, check the level and, if

necessary, top-up but never exceeding the MAX

level reference mark.N.B.THE ENGINE MUST BE HOT WHEN THE OIL IS CHANGED.

Recommended productsAGIP CITY HI TEC 4T Engine oil


MAIN - 43

SAE 5W-40 Synthetic oil that exceed the require-

ments of API SL, ACEA A3, JASO MA specifica-

tions

Locking torques (N*m)Engine oil drainage plug 24 to 30

Check

This operation must be carried out with the engine

cold and following the procedure below:

1. Place the vehicle on its centre stand and on flat

ground.

2. Unscrew the cap/dipstick «A», dry it with a clean

cloth and reinsert it, screwing it all the way

down.

3. Remove the cap/dipstick again and check that

the level is between the min and max. marks; top-

up, if required.

The MAX level reference mark indicates the

amount of oil in the engine. If the check is carried

out after the vehicle has been used, and therefore

with a hot engine, the level line will be lower; in

order to carry out a correct check, wait at least 10

minutes after the engine has been stopped so as

to get the correct level.

CharacteristicEngine oil1.30 l


MAIN - 44

Oil top-up

The oil should be topped up after having checked

the level and in any case by adding oil without

ever exceeding the MAX. level.

Restoration of the level from MIN to MAX requires

approximately 200 cc.

Engine oil filter

The cartridge filter must be replaced every time the oil is changed. Use new oil of the recommended

type for topping up and changing purposes.

Make sure the pre-filter and drainage plug O-rings are in good conditions. Lubricate them and refit the

mesh filter and the oil drainage plug, screwing them up to the prescribed torque. Refit the new cartridge

filter being careful to lubricate the O-ring before fitting it. Change the engine oil.

Recommended productsAGIP CITY HI TEC 4T Engine oil

SAE 5W-40 Synthetic oil that exceed the requirements of API SL, ACEA A3, JASO MA specifications

Oil pressure warning light

Warning light (low oil pressure)

The vehicle is equipped with a warning light on the

instrument panel that lights up when the key is

turned to the «ON» position. However, this light

should switch off once the engine has been star-

ted.

If the light comes on during braking, at idling

speed or while turning, it is necessary to first

switch off the engine and then to check the oil

level and the lubrication system


MAIN - 45

Cooling system

Adding engine coolant.

Check coolant level when the engine is cold as in-

dicated in the scheduled maintenance table, fol-

lowing the steps below:

Place the scooter on its centre stand and on flat

ground.

- Remove the expansion tank cover «A».CAUTIONDO NOT EXCEED THE MAX. LEVEL WHEN FILLING SO ASTO AVOID THE COOLANT ESCAPING FROM THE EXPAN-SION TANK WHEN THE VEHICLE IS IN USE.

Recommended productsAGIP PERMANENT SPEZIAL CoolantMonoethylene glycol based antifreeze solution,

CUNA NC 956-16

- Top up if the fluid level is below the mark «3».

-The coolant consists of an ethylene glycol and

corrosion inhibitor based 50% de-ionised water-

antifreeze solution mix.CAUTIONDO NOT EXCEED THE MAX. LEVEL WHEN FILLING SO ASTO AVOID THE COOLANT ESCAPING FROM THE EXPAN-SION TANK WHEN THE VEHICLE IS IN USE.

Recommended productsAGIP PERMANENT SPECIAL coolantMonoethylene glycol-based antifreeze fluid, CU-

NA NC 956-16

Braking system


MAIN - 46

Level check

- Position the vehicle on a flat surface and on the

centre stand.

- Check the brake fluid level via the special indi-

cator located on the pump.

N.B.

THE LEVEL TENDS TO DROP AS THE BRAKE PADS GET WORN, A MINIMUM LEVEL SHOULDNOT BE REACHED. IF THE LEVEL IS TOO LOW, CHECK AND FIX THE SYSTEM SEALS, IF RE-QUIRED. TOP UP THE PUMP RESERVOIR, IF REQUIRED, CONSIDERING THAT THE "MAX."LEVEL MUST ONLY BE OBTAINED WITH NEW PADS.

Top-upCAUTION

ONLY USE DOT 4-CLASSIFIED BRAKE FLUID.

Proceed as follows:

- Position the vehicle on a flat surface and on the

centre stand.

- Remove the tank cap by removing the two

screws, remove the gasket and top up using only

the liquid specified without exceeding the maxi-

mum level.

CAUTION

AVOID CONTACT OF THE BRAKE FLUID WITH YOUR EYES, SKIN, AND CLOTHING. IN CASEOF ACCIDENTAL CONTACT, WASH WITH WATER.WARNING


MAIN - 47

BRAKE CIRCUIT FLUID IS VERY CORROSIVE; DO NOT LET IT COME INTO CONTACT WITHPAINTED PARTS.WARNING

THE BRAKE FLUID IS HYGROSCOPIC, THAT IS, IT ABSORBS MOISTURE FROM THE SUR-ROUNDING AIR. IF THE HUMIDITY IN THE BRAKING FLUID EXCEEDS A CERTAIN VALUE, ITWILL LEAD TO INEFFICIENT BRAKING; FOR THIS REASON, NEVER USE BRAKING FLUIDFROM CONTAINERS THAT HAVE ALREADY BEEN OPENED, OR PARTIALLY USED.

Characteristicprescribed fluid:

AGIP BRAKE FLUID DOT 4

Under normal climatic conditions, the brake fluid should be replaced following the given instructions.N.B.

SEE THE BRAKING SYSTEM CHAPTER WITH REGARD TO THE CHANGING OF BRAKE FLUIDAND THE BLEEDING OF AIR FROM THE CIRCUITS.

Headlight adjustment

- Place the vehicle in use conditions, with tyres inflated to the prescribed pressure on flat ground at 10

m from a white screen placed in dim light.

- Make sure that the scooter axle is perpendicular to the screen.

- Turn the headlight on and check that the limit of the light beam projected onto the screen does not

exceed 9/10 of the headlight centre height from the ground and that it is not less than 7/10.

- Otherwise, adjust the right headlight by the screw

shown in the figure, which can be accessed by re-

moving the front shield connecting member.N.B.THE ABOVE PROCEDURE COMPLIES WITH THE EURO-PEAN STANDARDS REGARDING MAXIMUM AND MINI-MUM HEIGHT OF LIGHT BEAMS. REFER TO THE STATU-TORY REGULATIONS IN FORCE IN EVERY COUNTRYWHERE THE VEHICLE IS USED.


MAIN - 48

INDEX OF TOPICS

TROUBLESHOOTING TROUBL

This section makes it possible to find what solutions to apply when troubleshooting.

For each failure, a list of the possible causes and pertaining operations is given.

Engine

Excessive oil consumption/Exhaust smoke

EXCESSIVE CONSUMPTIONPossible Cause Operation

Wrong valve adjustment Adjust the valve clearance properlyOverheated valves Remove the head and the valves, grind or replace the valves

Misshapen/worn valve seats Replace the head unitWorn cylinder, Worn or broken piston rings Replace the piston cylinder assembly or piston rings

Worn or broken piston rings or piston rings that have not beenfitted properly

Replace the piston cylinder unit or just the piston rings

Oil leaks from the couplings or from the gaskets Check and replace the gaskets or restore the coupling sealWorn valve oil seal Replace the valve oil sealWorn valve guides Check and replace the head unit if required

Insufficient lubrication pressure

LOW LUBRICATION PRESSUREPossible Cause Operation

By-Pass remains open Check the By-Pass and replace if required. Carefully clean theBy-Pass area.

Oil pump with excessive clearance Perform the dimensional checks on the oil pump componentsOil filter too dirty Replace the cartridge filterOil level too low Restore the level by adding the recommended oil type.

Transmission and brakes

Clutch grabbing or performing inadequately

IRREGULAR CLUTCH PERFORMANCE OR SLIPPAGEPossible Cause Operation

Faulty clutch Check that there is no grease on the masses. Check that theclutch mass faying surface with the bell is mainly in the centrewith equivalent characteristics on the three masses. Check thatthe clutch housing is not scored or worn in an anomalous way

Insufficient braking

INEFFICIENT BRAKING SYSTEMPossible Cause Operation

Inefficient braking system Check the pad wear (1.5 min). Check that the brake discs arenot worn, scored or warped. Check the correct level of fluid inthe pumps and change brake fluid if necessary. Check there isno air in the circuits; if necessary, bleed the air. Check that the

front brake calliper moves in axis with the disc.Fluid leakage in hydraulic braking system Failing elastic fittings, plunger or brake pump seals, replace

Troubleshooting MSS Nexus 125 i.e. (2008)

TROUBL - 50

Possible Cause OperationBrake disc slack or distorted Check the brake disc screws are locked; measure the axial shift

of the disc with a dial gauge and with wheel mounted on thevehicle.

Brakes overheating

BRAKE OVERHEATPossible Cause Operation

Defective plunger sliding Check calliper and replace any damaged part.Brake disc slack or distorted Check the brake disc screws are locked; use a dial gauge and

a wheel mounted on the vehicle to measure the axial shift ofthe disc.

Clogged compensation holes on the pump Clean carefully and blast with compressed airSwollen or stuck rubber gaskets Replace gaskets.

Steering and suspensions

Heavy steering

STEERING HARDENINGPossible Cause Operation

Steering hardening Check the tightening of the top and bottom ring nuts. If irregu-larities in turning the steering continue even after making theabove adjustments, check the seats on which the ball bearingsrotate: replace them if they are recessed or if the balls are flat-

tened.

Excessive steering play

EXCESSIVE STEERING CLEARANCEPossible Cause Operation

Torque not conforming Check the tightening of the top and bottom ring nuts. If irregu-larities in turning the steering continue even after making theabove adjustments, check the seats on which the ball bearingsrotate: replace them if they are recessed or if the balls are flat-

tened.

Noisy suspension

NOISY SUSPENSIONPossible Cause Operation

Faults in the suspension system If the front suspension is noisy, check: the efficiency of the frontshock absorber; the condition of the ball bearings and relevantlock-nuts, the limit switch rubber buffers; and the movementbushings. In conclusion, check the tightening torque of the

wheel hub, the brake calliper, the shock absorber disc in theattachment to the hub and the steering tube.

MSS Nexus 125 i.e. (2008) Troubleshooting

TROUBL - 51

Suspension oil leakage

OIL LEAKAGE FROM SUSPENSIONPossible Cause Operation

Faulty or broken seals Replace the shock absorber Check the condition of wear of thesteering covers and the adjustments.

Troubleshooting MSS Nexus 125 i.e. (2008)

TROUBL - 52

INDEX OF TOPICS

ELECTRICAL SYSTEM ELE SYS

KEY

1. Injection ECU

2. Wheel turning sensor

3. Helmet compartment light bulb

4. Helmet compartment light switch

5. 12V 180W Socket

6. voltage regulator

7. 15A fuse

8. 15A fuse

9. key switch contacts

10. 7.5A fuse

11. 7.5A Fuse

12. low-beam light bulb 12V 55W

13. 7,5A fuse

14. 7.5A fuse

15. 7.5A fuse

16. Key switch contacts

17. diagnostics socket

18. coolants temperature sensor

19. stand button

20. engine stop switch

21. fuel pump

22. injector

23. lambda probe

24. hv coil

25. engine rpm sensor

26. water pump

27. immobilizer decoder

28. electric fan

29. electric fan remote control

30. 15A fuse

31. 15A fuse

32. electronic control unit remote control

33. electric control management device

34. turn indicator switch

35. Remote "MODE" button

36. oil pressure sensor.

Electrical system MSS Nexus 125 i.e. (2008)

ELE SYS - 54

37. Fuel level transmitter

38. turn indicator control device

39. left turn indicator bulbs

40. right turn indicator bulbs

41. analogue rpm indicator

42. 7.5A fuse

43. stop button

44. filament 21W of the bulb 12V-21/5W for rear stop light

45. starter button

46. start-up remote control

47. starter motor

48. battery

49. 30A fuse

50. light switch

51. high-beam light switch in passing mode

52. high-beam warning light

53. high-beam light remote control

54. High-beam light bulb12V 55W

55. magneto flywheel

56. instrument panel

57. pre-installation for anti-theft device

58. horn button

59. horn

60. tail lights and license plate light bulbs

KEY

Ar: Orange Az: Sky Blue Bi: White Bl: Blue Gi: Yellow Gr: Grey Ma: Brown Ne: Black Ro: Pink Rs:

Red Ve: Green Vi: Purple

MSS Nexus 125 i.e. (2008) Electrical system

ELE SYS - 55

Components arrangement


ELE SYS - 56

1. Remote control switches

Remove the legshield to reach it.

. High-beam light remote control

B. Electric fan remote control

C. Injection load remote control

2. Electrical control device

Remove the legshield to reach it.

3. Main fuses

To reach it, remove the battery cover placed in the helmet compartment.

4. Injection ECU

To reach it, remove the inspection compartment

placed in the helmet compartment.

5. Auxiliary fuses

Located in the helmet compartment.

6. Starter motor

Remove the helmet compartment to reach it.


ELE SYS - 57

7. Starter remote control

Remove the central chassis cover to reach it.

8. Stand button

Remove the left footrest to reach them.

9. Horn

To reach it, remove the lower cover.

10-11. Key switch/Immobilizer aerial

Remove the shield back plate to reach it.

12. Battery

To reach it, remove the battery cover placed in the helmet compartment.


ELE SYS - 58

13. HV coil

Remove the right side fairing to reach it.

14. Magneto flywheel

The connector is located near the fuel pump. To

reach it, remove the central chassis cover.

15. Fuel pump

16. Oil pressure sensor

On the engine, on the right-hand side of the vehi-

cle.


ELE SYS - 59


To reach it, remove the central chassis cover. The

transmitter is integrated to the fuel pump.

18. Voltage regulator

To reach it, remove the lower cover.


In the front wheel, on the right-hand side.

20. Electric fan

Remove the radiator.

Conceptual diagrams


ELE SYS - 60

Ignition

KEY

1. Injection ECU

6. voltage regulator

8. 15A fuse


42. 7.5A fuse

43. stop button

44. filament 21W of the bulb 12V-21/5W for rear stop light

45. starter button


47. starter motor

48. battery

49. 30A fuse



ELE SYS - 61

Headlights and automatic starter section

7. 15A fuse

8. 15A fuse


10. 7.5A fuse

11. 7.5A Fuse

12.. Low-beam light bulb 12V 55W

13. 7,5A fuse

15. 7.5A fuse

16. . key switch contacts


34.. turn indicator switch

38. turn indicator control device

39. Left turn indicator bulbs

40. Right turn indicator bulbs

48. battery

50. Light switch

51. high-beam light switch in passing mode pressed

52 high-beam warning light

53. high-beam light remote control


ELE SYS - 62

54. high-beam light bulb 12V 55W

56. Instrument panel

60. tail lights and license plate light bulbs

Battery recharge and starting

KEY

1. Injection ECU

6. Voltage regulator

8. 15A fuse


42. 7.5A fuse

43. stop button

44.. 21W filament of the bulb 12V-21/5W for rear stop light

45. starter button


47. starter motor

48. battery

49. 30A fuse



ELE SYS - 63

Level indicators and enable signals section

KEY

1. Injection ECU


7. 15A fuse

8. 15A fuse


13. 7,5A fuse

15. 7.5A fuse


18. coolants temperature sensor

19. stand button


22. injector

23. lambda probe


27. Immobilizer decoder



35 Remote "MODE" button

36 oil pressure sensor.


ELE SYS - 64


41. analogue rpm indicator

48. battery

56. Instrument panel

Devices and accessories

KEY

1. Injection ECU

3. Helmet compartment light bulb

4. Helmet compartment light switch

5. 12V 180W socket

7. Fuse 15A

8. Fuse 15A


13. Fuse 7.5A

14. Fuse 7.5A


21. Fuel pump

28. Electric fan

29. Electric fan remote control

30. Fuse 15A

31. Fuse 15A

32. Electronic control unit remote control switch

39. Left turn indicator bulbs

40. Right turn indicator bulbs

47. Starter motor

48. Battery

57. Pre-installation for anti-theft device

58. Horn button

59. Horn

Checks and inspections


ELE SYS - 65

Immobiliser

The electric ignition system is fed with direct cur-

rent and is protected by an anti-theft immobilizer.

The ignition system consists of:

- an electronic control unit

- immobilizer aerial

- master and service keys with built-in transponder

- HV coil

- diagnosis LED

- decoder

The diagnosis LED also works as a blinking light

to deter theft. This function is activated every time

the key switch is set to «OFF», when the side

stand is lowered or the engine emergency cut-off

switch is set to «OFF». It remains activated for 48

hours in order not to affect the battery charge.

When the ignition switch is turned to «ON», the

deterring blinker function is deactivated. Subse-

quently, a flash confirms the switching to « ON».

The duration of the flash depends on the electronic

control unit program (see figure).

In case the LED turns off and remains so even

when switching over to «ON», check if:

- the battery is charged

- the 15A fuse (No. 2) is in working order.

If the deterring LED remains off, check the control

unit power supply as follows:

- Disconnect the control unit connector and check

if:

- There is battery voltage between terminal No. 6

(Red/White) and the ground lead.

- There is battery voltage between the terminal No.

6 (Red/White) and the terminal No. 26 (Negative)

as shown in the figure.


ELE SYS - 66

- There is battery voltage between the terminals

No. 5 and No. 8 with the key switch set to «ON»,

the side stand folded up and the emergency cut-

off switch set to «RUN».

If no faults are found, replace the control unit; oth-

erwise, check the wiring and the following compo-

nents:

- Emergency cut-off switch;

- Side stand contacts;

- Key switch contacts.

Virgin circuit

If the ignition system has not been programmed,

the engine can be started but it will run limited to

2000 rpm. When trying to accelerate, some evi-

dent loss of power may be felt.

Program the system with the MASTER (Brown)

and SERVICE (Black) keys as follows:

- Insert the MASTER key, turn it to "ON" and keep

it in that position for 2 seconds (limit values: 1 ÷ 3

seconds).

- Alternately insert all the available black keys and

turn each one of them to "ON" for 2 seconds.

- Insert the MASTER key again and turn it to "ON"

for 2 seconds.

The maximum time to change keys is 10 seconds.

A maximum of 7 (Black) service keys can be pro-

grammed at one time.

Sequence and times must be strictly observed or

it will be necessary to repeat the procedure from

the start.

Once the control unit has been programmed, the

decoder is inseparably matched with the MASTER

key transponder.

With this link established, it is now possible to en-

code new service keys, in the event of losses,


ELE SYS - 67

replacements, etc. Each new programming dele-

tes the previous one.

If a service key setting is lost, it is essential to

carefully check the efficiency of the high voltage

system:

Shielded cap resistance ~ 5000 Ω.

In any case it is advisable to use resistive spark

plugs.

Diagnostic codes

The flash indicating the switching to "ON" can be followed by a phase of programmed failure warnings.

That is, the led is off for 2 seconds, and then diagnosis codes are transmitted with 0.5-second flashes.

After the failure code indication, the LED remains on permanently to indicate that ignition is not possible.

Diagnostic code - 2 flashes

When the 2-flash code is detected, carry out the following checks:

- Check if the failure continues after changing key (MASTER key included). If the failure persists with

any key, disconnect the aerial connector from the decoder and check the aerial for continuity with the

recommended tool.

If non-conforming values are measured, replace the aerial.

If no failures are found in the aerial, replace the control unit.CAUTION

BEFORE PROGRAMMING THE NEW ELECTRONIC CONTROL UNIT CHECK THAT NO FAILURECODE IS INDICATED. THIS IS NECESSARY TO AVOID SPOILING A NEW CONTROL UNIT

Specific tooling020331Y Digital multimeter

Electric characteristicimmobilizer aerial

~ 7 ÷ 9 Ohm

2-FLASH CODE - Example with programmed control unit, no transponder and/or malfunctioning aerial.

Ignition disabled-Vehicle immobilised


ELE SYS - 68

Diagnostic code - 3 flashes

If the 3-flash code is detected, check if the failure occurs when the MASTER key in inserted into the

key switch.

- If the failure disappears when the MASTER key is used, proceed with coding a new service key (Blue).

- If the failure persists, it means that the MASTER key and the decoder are not linked; in this case,

replace the decoder and then encode the keys.

The immobilizer system is efficient when, after switching over to «ON», only a 0.7-sec flash is detected

(see diagram).

In this case, the engine can be started.

Example with programmed decoder, transponder,

programmed key and working aerial. The ignition

is enabled (regular use conditions)

3-FLASH CODE - Example with programmed decoder, aerial working properly and unknown trans-

ponder code. Ignition disabled-Vehicle immobilised

Ignition circuit

Once the immobilizer system is enabled, the HV coil and the signals from the Pick-Up will produce a

spark in the spark plug.

The battery provides the basic power supply. The system is adjusted so that the start-up system im-

mediately detects an eventual battery voltage drop, but this is practically irrelevant for the ignition

system.

The Pick-Up is connected to the control unit by a single cable; then, for the ground circuit, the control

unit is connected to the Pick-Up by the chassis and the engine ground lead.

To avoid disturbances in the ignition system during start-up, it is very important that the engine-chassis

ground connection bonding is efficient.


ELE SYS - 69

No spark plug

Once the lack of power to the spark plug has been

detected and the LED indicates it can be ignited,

follow this procedure:

- Pick-Up check.

Disconnect the control unit connector and check

the resistance value between terminal No. 13

(Red) and terminal No. 15 (White). Check the Pick-

Up and its power line:

Electric characteristicPick-up resistance value105 ÷ 124 Ohm

If a break in the circuit is found, check again the flywheel and the engine ground connectors (see engine

manual). If non-conforming values are measured, replace the Pick-Up; otherwise, repair the cable har-

ness.

In case conforming values are measured, try replacing the control unit (without programming) and make

sure the failure has been solved by checking sparks are produced in the spark plug; only then program

the control unit.

- HV primary coil check

Disconnect the connector of the HV coil and check

again the HV primary coil directly on the positive

and negative terminals. If non-conforming values

are measured, repair the cable harness or else re-

place the HV coil.

Electric characteristicHigh voltage coil primary resistance value~ 1 ohm

HV coil secondary check

Disconnect the spark plug cap from the HV cable

and measure the resistance between the HV cable

terminal and the HV coil negative terminal (see

figure).

If non-conforming values are measured, replace

the HV coil. To carry out a more complete diagno-

sis, check the peak voltage with the multimeter

adaptor.


ELE SYS - 70

Electric characteristicHigh voltage coil secondary resistance value~ 8,000 ± 300 ohm

Pick-Up.

- Disconnect the control unit connector and con-

nect the positive terminal to connector No. 13 and

the negative terminal to connector No. 15 (see fig-

ure).

- The multimeter end of a scale should be 200V.

Use the start-up system to run the engine and

measure the voltage produced by the Pick-Up.

- Replace the Pick-Up if non-conforming values

are measured.N.B.THE MULTIMETER MUST BE SELECTED TO DETECTCONTINUOUS VOLTAGE.

Specific tooling020409Y Multimeter adaptor - Peak voltage de-tection

Electric characteristicVoltage value> 5 Volt

- HV coil

With the control unit and HV coil connected, meas-

ure the voltage of the coil primary during the start-

up test with the voltage peak adaptor and con-

necting the positive terminal to the ground one and

the negative to the coil positive connector.

If non-conforming values are measured, replace

the control unit.N.B.THE PLASTIC CAP OF THE POSITIVE TERMINAL ON THEHV COIL PRIMARY IS BLACK AND THE NEGATIVE TER-MINAL ONE IS GREEN.

Electric characteristicHigh voltage coil voltage valueHigh voltage coil voltage value: > 100 Volt


ELE SYS - 71

Stator check

Disconnect the connector from the voltage regu-

lator and check there is continuity between any

yellow cable and the other two cables.

Electric characteristicOhm value:0.7 ÷ 0.9 Ohm

Also check that all yellow cables are insulated from

the ground connection.

If non-conforming values are detected, repeat the

checks directly to the stator. In case of further rep-

etitions of incorrect values replace the stator or

repair the wiring.

Voltage regulator check

With a perfectly charged battery and lights off,

measure voltage at the battery poles with a high

running engine.

The voltage should not exceed 15.2 Volt.

In case higher voltages are detected, replace the

regulator.

In case of voltage values lower than 14 Volt, check

the stator and the corresponding cable harness.


ELE SYS - 72

Recharge system voltage check

The recharge circuit is provided with a three-phase

generator with permanent magneto flywheel.

The generator is directly connected to the voltage

regulator.

In turn, the voltage regulator is directly connected

to the ground connection and to the battery posi-

tive terminal passing through the 30A protection

fuse (No. 6).

This system therefore requires no connection to

the key switch.

The three- phase generator provides good re-

charge power and at low revs, a good compromise

is achieved between generated power and idle

stability. For this reason, it is very important that

the idle speed is adjusted as prescribed.

Connect an ammeter induction clamp to the volt-

age regulator positive terminal, measure the bat-

tery voltage and turning on the vehicles lights with

engine off, wait for the voltage to set at about 12

V. Start the engine and measure the current gen-

erated by the system with lights on and a high

running engine.

In case the generated current value is lower than

10A, repeat the test using a new regulator and/

stator alternatively.

Turn signals system check

Instrument panel power supply check:

- Disconnect the instrument panel connector and check that there is battery voltage between terminal

No. 11/20 (White-Red) and the ground connection.

-Check that the same happens between terminal No. 11/20 and terminal No. 16/20 (Black).

- Repeat the check between terminal No. 13/20 (White-Black) and terminal No. 16/20 with the key switch

set to «ON», the side stand should be raised and the emergency switch set to «RUN».

if there is no voltage, check cable harness, and that 7.5A fuses (No 8 and 7) are connected and in good

conditions. Otherwise, proceed as follows:


ELE SYS - 73

- Connect the instrument panel terminal No 18/20 to ground and check that the right turn indicators turn

on.

- Repeat the check with terminal No 19/20 making sure that the left turn indicators turn on.

If no lights turn on, replace the instrument panel because it is faulty. If they turn on, carry out the following

checks:

- Check for the continuity between terminals No. 3 and No. 2 of the electric control management device

with the turn indicator switch activated to the right.

- Repeat the test between terminals No 5 and No 4 with the turn indicator switch activated to the left.

If there is no continuity, check the connection cable harness between the instrument panel, the electric

control management device and the turn indicator switch, then repeat the test.

If there is still no continuity between the terminals, replace the electric control management device

because it is faulty. If there is continuity, replace the turn indicator switch because it is certainly dam-

aged.

Lights list

BULBSSpecification Desc./Quantity

1 High/low beam light bulb Type: Halogen (H7)Power: 12V - 55W

Quantity: 22 Front position light bulb Type: Incandescent (W2.1x9.5d)

Power: 12V - 5WQuantity: 2

3 Rear turn indicator light bulb Type: Incandescent (BAU 15s)Power: 12V - 10 W

Quantity: 1 RHS + 1 LHS4 Front turn indicator bulb Type: Incandescent (W2.1x9.5d)

Power: 12V - 5 WQuantity: 2 RHS + 2 LHS

5 Tail light and stop light bulb Type: Incandescent (W2.1x9.5d)Power: 12V - 21/5W

Quantity: 16 License plate bulb Type: Incandescent (W2.1 x 9.5D)

Power: 12V - 5WQuantity: 1

7 Helmet compartment light bulb Type: Incandescent (SV 8.5)Quantity: 1

Power: 12V - 5W


ELE SYS - 74

Fuses

The electric system is fitted with 2 fuse boxes:

Fuse box «A» 5 fuses located in the helmet com-

partment near the battery.

Fuse box«B» 6 fuses located in the helmet com-

partment near the plug socket.

Replace fuses using adequate pliers supplied in

the tool kit.

The chart shows the position and specifications of

the fuses in the vehicle.CAUTION

BEFORE REPLACING A BLOWN FUSE, FIND AND SOLVETHE FAILURE THAT CAUSED IT TO BLOW. NEVER TRYTO REPLACE THE FUSE WITH ANY OTHER MATERIAL(E.G., A PIECE OF ELECTRIC WIRE).

FUSESSpecification Desc./Quantity

1 Fuse No. 1 Capacity: 30 AProtected circuits: Battery recharge circuit.

2 Fuse No. 2 Capacity: 15AProtected circuits: Fuse n°10, plug socket, helmet

compartment lighting.Live: Fuse No. 11

3 Fuse No. 3 Capacity: 15AProtected circuits: Electric fan (via remote control)

4 Fuse No. 4 Capacity: 15ALive: Fuses No.6-7-8-9-.

5 Fuse No. 5 Capacity: 10 AProtected circuits: Injection load (via remote control),

battery ECU, water pump.6 Fuse No. 6 Capacity: 7.5 A

Protected circuits: Low-beam light.7 Fuse No. 7 Capacity: 7.5 A

Protected circuits: High-beam light.8 Fuse No. 8 Capacity: 7.5 A

Protected circuits: start-up circuit, horn.


ELE SYS - 75

Specification Desc./Quantity9 Fuse No. 9 Capacity: 7.5 A

Protected circuits: Tail lights, plate light bulbs, Instru-ment panel lighting.

10 Fuse No. 10 Capacity: 7.5 AProtected circuits: Pre-installation for anti-theft device,

battery-powered instrument panel.11 Fuse No. 11 Capacity: 7.5 A

Protected circuits: Immobilizer aerial, electric fan re-mote control, Injection load remote control, electric con-trol management device, direct power supply to instru-ment panel and control unit, pre-installation for anti-theft

device.

Dashboard

The digital display has two service symbols:

SERVICE:

The lamp should come on after reaching 1,000 km,

then every 6,000 km or 1 year after the last acti-

vation.

BELT:

This lamp should turn on and flash every 6,000 km.

• Press buttons "MODE" and "ODO/SET" simultaneously at the moment you turn the key to

"ON" for more than 3 seconds: The "BELT" symbol starts to flash.

• Pressing the button "MODE" for less than 1 second displays the symbols in turn. The se-

lected symbol remains lit.

• Pressing button "MODE" for longer than 3 seconds resets the kilometre reading for the

symbol selected, in "SERVICE" mode the date is also reset.N.B.

• AT THE MOMENT THE DATE IS RESET, THE "SERVICE" SYMBOL IS ACTIVATEDAGAIN.

• PERFORM THE RESET PROCEDURE ONLY AT THE MOMENT OF DELIVERY OF THESCOOTER TO THE CUSTOMER IN ORDER THAT THIS SYMBOL SIGNALS THE NEEDFOR THE FIRST SERVICE IN RELATION TO THE DISTANCE TRAVELLED AND THETIME SINCE THE ACTIVATION.


ELE SYS - 76

The instrument Panel recognises the vehicle en-

gine type (125 cm³, 250 cm³, 500 cm³); according

to the 12-way connector configuration of the con-

necting clamp between the electric system Cable

harness and the Instrument Panel.

INSTRUMENT PANEL COMMON TERMINAL DESCRIPTIONSpecification Desc./Quantity

Pins No 5 and No 12 jumped Nexus 500Pins No 6 and No 12 jumped Nexus 250

Pins No 5, No. 6 and No. 12 jumped Nexus 125

Sealed battery

If the vehicle is provided with a sealed battery, the only maintenance required is the check of its charge

and recharging, if necessary.

These operations should be carried out before delivering the vehicle, and on a six-month basis while

the vehicle is stored in open circuit.

Besides upon pre-delivery it is therefore necessary to check the battery charge and recharge it, if re-

quired, before storing the vehicle and afterwards every six months.

INSTRUCTIONS FOR THE BATTERY REFRESH AFTER OPEN-CIRCUIT STORAGE

1) Voltage check

Before installing the battery on the vehicle, check the open circuit voltage with a standard tester.

- If voltage exceeds 12.60 V, the battery can be installed without any renewal recharge.

- If voltage is below 12.60 V, a renewal recharge is required as explained in 2).

2) Constant voltage battery charge mode

- Constant voltage charge equal to 14.40 to 14.70V

- Initial charge voltage equal to 0.3 to 0.5 for Nominal capacity

- Charge time:

10 to 12 h recommended


ELE SYS - 77

Minimum 6 h

Maximum 24 h

3) Constant current battery charge mode

- Charge current equal to 1/10 of the nominal capacity of the battery

- Charge time: 5 hCAUTION

NEVER USE FUSES WITH A CAPACITY HIGHER THAN THAT RECOMMENDED. THE USE OF AFUSE OF UNSUITABLE CAPACITY MAY RESULT IN SERIOUS DAMAGES TO THE WHOLE VE-HICLE OR EVEN CAUSE A FIRE.CHARGE THE BATTERY BEFORE USE TO ENSURE OPTIMUM PERFORMANCE. INADEQUATECHARGING OF THE BATTERY WITH A LOW ELECTROLYTE LEVEL BEFORE IT IS FIRST USEDSHORTENS THE LIFE OF THE BATTERY.IF THE VEHICLE IS NOT USED FOR SOME TIME (1 MONTH OR MORE) THE BATTERY NEEDSTO BE RECHARGED PERIODICALLY. THE BATTERY RUNS DOWN COMPLETELY IN THECOURSE OF THREE MONTHS. IF IT IS NECESSARY TO REFIT THE BATTERY IN THE vehicle,BE CAREFUL NOT TO REVERSE THE CONNECTIONS TAKING INTO ACCOUNT THAT THEGROUND WIRE (BLACK) MARKED (-) MUST BE CONNECTED TO THE - NEGATIVE TERMINAL,WHEREAS THE OTHER TWO RED WIRES MARKED (+) MUST BE CONNECTED TO THE TERMI-NAL MARKED WITH THE +POSITIVE SIGNWARNING

WHEN THE BATTERY IS REALLY FLAT (WELL BELOW 12.6V) IT MIGHT OCCUR THAT 5 HOURSOF RECHARGING ARE NOT ENOUGH TO ACHIEVE OPTIMAL PERFORMANCE.GIVEN THESE CONDITIONS IT IS HOWEVER ESSENTIAL NOT TO EXCEED 8 HOURS OF CON-TINUOUS RECHARGING SO AS NOT TO DAMAGE THE BATTERY ITSELF.

The battery should always be kept clean, especially on its top side, and the terminals should be coated

with Vaseline.

Normal bench charging must be carried out using the specific battery charger 020333Y (single) or

020334 (multiple), setting the battery charge selector to the type of battery that needs recharging (i.e.,

at a current equal to 1/10 of the battery rated capacity). Connections to the power supply source must

be implemented by connecting corresponding poles (+ to + and - to - ).

Battery installation

VRLA battery (valve-regulated lead-acid battery) Maintenance Free (MF)WARNING

BATTERY ELECTROLYTE IS TOXIC AND IT MAY CAUSE SERIOUS BURNS. IT CONTAINS SUL-PHURIC ACID. AVOID CONTACT WITH YOUR EYES, SKIN AND CLOTHING. IF COMING INTOCONTACT WITH EYES OR SKIN, WASH ABUNDANTLY WITH WATER FOR APPROX. 15 MIN.AND SEEK IMMEDIATE MEDICAL ATTENTION.IN THE EVENT OF ACCIDENTAL INGESTION OF THE LIQUID, IMMEDIATELY DRINK LARGEQUANTITIES OF WATER OR MILK, MAGNESIUM MILK, BATTERED EGG OR VEGETABLE OIL.SEEK IMMEDIATE MEDICAL ATTENTION.BATTERIES PRODUCE EXPLOSIVE GASES; KEEP CLEAR OF NAKED FLAMES, SPARKS ORCIGARETTES; VENTILATE THE AREA WHEN RECHARGING INDOORS.ALWAYS WEAR EYE PROTECTION WHEN WORKING IN THE PROXIMITY OF BATTERIES.KEEP OUT OF REACH OF CHILDREN


ELE SYS - 78

1) Battery preparation

Position the battery on a flat surface. Remove the

adhesive sheet closing cells and proceed as quick-

ly as possible to run the subsequent activation

phases.

2) Electrolyte preparation.

Remove the container of the electrolyte from the

pack. Remove and preserve cover strips from the

container, in fact, the strip will later be used as a

closing cover.

Note: Do not pierce the sealing of the container or

the container itself because inside there is sulphu-

ric acid.

3) Procedure for filling the battery with acid.

Position the electrolyte container upside down with

the six areas sealed in line with the six battery filler

holes. Push the container down with enough force

to break the seals. The electrolyte should start to

flow inside the battery.

Note: Do not tilt the container to prevent the flow

of electrolyte from pausing or stopping.

4) Control the flow of electrolyte

Make sure air bubbles are rising from all six filling holes. Leave the container in this position for 20

minutes or more.

Note:If there are no air bubbles coming out of the filling holes, lightly tap the bottom of the container

two or three times. Do not remove the container from the battery.

5) Take out the container.

Make sure all the electrolyte in the battery is drained. Gently tap the bottom of the container if electrolyte

remains in the container. Now, gently pull the container out from the battery, only do this when the

container is completely empty, and proceed immediately to the next point.

6) Battery closing.

Insert the airtight cover strips into the filling holes. Press horizontally with both hands and make sure

that the strip is levelled with the top part of the battery.


ELE SYS - 79

Note:To do this, do not use sharp objects that could damage the closing strip, use gloves to protect

your hands and do not bring your face close to the battery.

The filling process is now complete.

Do not remove the strip of caps under any circumstances, do not add water or electrolyte.

Place the battery down for 1 to 2 hours prior to the charging from the battery.

7) Recharging the new battery

With the above-mentioned procedure, the battery

will have gained around 70% - 75% of its total

electrical capacity. Before installing the battery on

the vehicle, it must be fully charged and then must

be recharged.

If the battery is to be installed on the vehicle

prior to this pre-charged one, the battery will

not be able to exceed 75% charge without jeop-

ardising its useful life on vehicle.

The dry charge battery MF like the completely loa-

ded YTX, must have a no-load voltage between

12.8 - 13.15 V Bring the battery to full charge, us-

ing the 020648Y battery charger:

a - select the type of battery with the red switch on

the left of the panel battery charger panel

b - select NEW on the yellow timer

c - connect the clamps of the battery charger to the

battery poles (black clamp to negative pole (-) and

red clamp to positive pole (+)).

d - Press the red button, as shown in figure.


ELE SYS - 80

e - Press the "MF" black button to activate the bat-

tery recharge Maintenance Free as shown in fig-

ure.

f - Check the ignition of the green LED indicated

with a red arrow in figure.

g - The activation cycle of the new battery lasts for

30 minutes after the ignition of the recharge LED

has taken place

h - Disconnect the clamps from the battery and

check the voltage, if voltages are detected of less

than 12.8 V, proceed with a new recharge of the

battery starting from point c of the recharge pro-

cedure of the new battery, otherwise go to point i

i - The battery is now completely activated, disconnect the battery charger from the fuel supply grid,

disconnect the clamps from the battery and proceed to fitting the battery on the vehicle.


ELE SYS - 81

Connectors

INSTRUMENT PANEL CONNECTOR

1. To the wheel turning sensor (Red)

2. To the wheel turning sensor (Blue)

3. To the wheel turning sensor (Grey-Black)

4. Panel lighting and headlight warning light (Yel-

low-Black)

5. Rpm indicator signal (Green)

6. Thermistor signal (Orange)

7. Ground lead (Sky blue-Black)

8. . Oil pressure signal (White)

9. Right turn indicator warning light (White-Blue)

10. Left turn indicator warning light (Pink)

11. +Battery (Red-Black)

12. Immobilizer LED (Grey-Yellow)

13. +Live (White-Black)

14. To electric control management device (Grey )

15. Fuel level signal (White-Green)

16. Ground lead (Black)

17. Injection telltale light (Brown-White)

18. To electric control management device (Blue)

19. To electric control management device (Pink-

Black)

20. Not used

TONE WHEEL CONNECTOR

1. To the instrument panel (Blue)

2. To the instrument panel (Grey-Black)

3. To the instrument panel (Red)


ELE SYS - 82

CONTROL UNIT CONNECTOR

1. Injection telltale light (Brown-White)

2. Rpm indicator (Green)

3. Not connected

4. Lambda probe negative (Light blue-Black)

5. Live power supply (White-Black)

6. Live power supply (White-Red)

7. Immobilizer aerial (Orange-White)

8. Electric fan remote control (Green-White)

9. temperature sensor (Yellow-Pink)

10. Not connected

11. Lambda probe positive (Light blue-Yellow)

12. Engine stop switch (Orange)

13. Rpm sensor positive (Red)

14. Injector (Red-Yellow)

15. Rpm sensor negative (White)

16. Diagnosis (Orange-Black)

17. Immobilizer warning light (Grey-Yellow)

18. Stand button (Brown-Red)

19. Not connected

20. Injection load remote control (Black-Purple)

21. Not connected

22. HV coil (Pink-Black)

23. Not connected

24. Start-up enabling switch (Green-Blue)

25. Not connected


ANTITHEFT CONNECTOR

1. Left turn indicators (Pink)

2. Right turn indicators (White-Blue)




6. Helmet compartment light (Blue-Yellow)

7. Not connected

8. Not connected


ELE SYS - 83

VOLTAGE REGULATOR CONNECTOR

1. Battery positive terminal (Red-White)


3. Battery positive terminal (Red-White)



ELE SYS - 84

INDEX OF TOPICS

ENGINE FROM VEHICLE ENG VE

This section describes the operations to carry out when removing the engine from the vehicle.

Exhaust assy. Removal

- Remove the Lambda probe from its support and

disconnect it.

- Undo the two exhaust manifold fixings on the

head. To unscrew the nuts that fix the silencer

flange to the head properly, use a jointed wrench

that allows, according to the travel direction, to get

also at the right nut. That is difficult to do with a

traditional straight wrench.

- Undo the three screws that fix the silencer to the

supporting arm.

- Remove the full silencer unit.

Remove the lambda probe from the manifold.

Engine from vehicle MSS Nexus 125 i.e. (2008)

ENG VE - 86

CAUTION: SHOULD IT BE NECESSARY TO REMOVE ONLY THE SILENCER TIP, ALWAYS RE-

PLACE THE GRAPHITE GASKET BETWEEN STUB AND TIP.

Removal of the engine from the vehicleCAUTION

THIS OPERATION MUST BE CARRIED OUT WHEN THE ENGINE IS COLD.CAUTION

SUPPORT THE VEHICLE ADEQUATELY.

- Remove the central tunnel.

- Remove the full muffler unit.

- Remove the air filter.

- Working on the vehicle right side, remove the

coolant inlet pipes and empty the system.N.B.LET THE COOLANT DRAIN INTO A CONTAINER OF ADE-QUATE CAPACITY.

CharacteristicCooling system fluid1.75 l

- Remove the tube from the spark plug.

MSS Nexus 125 i.e. (2008) Engine from vehicle

ENG VE - 87

- Remove the coolant outlet pipe from the engine.

- Disconnect the fuel pipe and the fitting to the

control unit.

- Disconnect the connector of the injector.

- Disconnect the coolant temperature sensor.

- Disconnect the control unit connector


ENG VE - 88

- Remove the clamp indicated and slide the throttle

body from the manifold.

- Unscrew the positive and negative cable har-

nesses of the starter motor.

- Disconnect the throttle grip cables by undoing the

set screws.

- Disconnect the oil minimum pressure sensor.


ENG VE - 89


- Disconnect the voltage regulator connector and

release the cable harness.

- Disconnect the power connector from the water

pump and release the cable harness.

- Take out the ground retainer on the engine and

remove the clamp by pulling.

- Remove the rear left shock absorber lower re-

tainer.


ENG VE - 90

- Remove the pin fixing the engine to the swinging

arm.

- The engine is now free.

When refitting the engine onto the vehicle, carry out the removal operations but in reverse order and

respect the tightening torques shown in the Specifications Chapter.

- Check the engine oil level and if necessary, top it up with the recommended type.

- Fill and bleed the cooling circuit.

- Check accelerator and electric devices for correct functioning.CAUTION

PAY PARTICULAR ATTENTION TO POSITIONING THE THROTTLE CONTROL TRANSMISSIONPROPERLY.


ENG VE - 91

INDEX OF TOPICS

ENGINE ENG

This section describes the operations to be carried out on the engine and the tools to be used.

Automatic transmission

Transmission cover

- Remove the air duct.

- With the specific tool lock the driven pulley, undo

the indicated nut and collect the washer.

Specific tooling020423Y Driven pulley lock wrench

- Undo the eleven fixings screws to the engine and

remove the transmission coverN.B.WHEN YOU ARE REMOVING THE TRANSMISSION COVERYOU MUST BE CAREFUL NOT TO DROP THE CLUTCHHOUSING.

Air duct

- Unscrew the two screws «1» fixing the air filter to

the engine.


crankcase cover «3».

MSS Nexus 125 i.e. (2008) Engine

ENG - 93


transmission housing filter cover «5».

- Take out the filtering element «6» from the cover.

Removing the driven pulley shaft bearing

- Remove the clip from the inside of the cover.

- Remove the bearing from the crankcase by

means of:

Specific tooling020376Y Adaptor handle

020375Y 28 x 30 mm adaptor

020412Y 15-mm guide

Refitting the driven pulley shaft bearing

- Heat the crankcase from the inside.

- Insert the bearing in its seat.

- Refit the Seeger ring.CAUTIONUSE AN APPROPRIATE SUPPORT TO AVOID DAMAGINGTHE COVER SURFACE.N.B.ALWAYS REPLACE THE BEARING WITH A NEW ONEUPON REFITTING.

Specific tooling

Engine MSS Nexus 125 i.e. (2008)

ENG - 94



020412Y 15-mm guide

Removing the driven pulley

- Remove the stationary driving half-pulley and the

clutch housing.

- Remove the driven pulley together with the belt.

Inspecting the clutch drum

- Check that the clutch housing is not worn or dam-

aged.

- Measure the clutch housing inside diameter.

CharacteristicMax. value clutch housingMax. value: Ø 134.5 mm

clutch housing standard valueStandard value: Ø 134 - 134.2 mm

Checking the bell working surface eccentricity

- Install the bell on a driven pulley shaft using 2

bearings (inside diameter: 15 and 17 mm).

- Lock with the original spacer and nut.

- Place the bell/shaft unit on the support to check

the crankshaft alignment.


ENG - 95

- Using a feeler dial gauge and the magnetic base,

measure the bell eccentricity.

- Repeat the measurement in 3 positions (Central,

internal, external).

- If faults are found, replace the bell.

Specific tooling020074Y Support base for checking crankshaftalignment


Characteristicclutch housing inspection: Limit eccentricity.Admissible limit eccentricity: 0.15 mm

Removing the clutch

Fit the driven pulley spring compressor specific

tool with medium length pins screwed in position

«C» on the tool internal side.

- Introduce the adapter ring 11 with the chamfering

facing the inside of the tool.

- Fit the driven pulley unit on the tool with the in-

sertion of the 3 pins in the ventilation holes in the

mass holder support.

- Make sure that the clutch is perfectly inserted into

the adapter ring before proceeding to loosen/tight-

en the clutch nut.

- Use the special 46x55 wrench component 9 to

remove the nut fixing the clutch in place.

- Dismantle the driven pulley components (Clutch

and spring with its plastic holder)CAUTIONTHE TOOL MUST BE FIRMLY FIXED IN THE CLAMP ANDTHE CENTRAL SCREW MUST BE BROUGHT INTO CON-TACT WITH THE TOOL. EXCESSIVE TORQUE CAN CAUSETHE SPECIFIC TOOL TO BUCKLE.

Specific tooling020444Y011 adapter ring

020444Y009 wrench 46 x 55

020444Y Tool for fitting/ removing the drivenpulley clutch


ENG - 96

Inspecting the clutch

- Check the thickness of the clutch mass friction

material.

- The masses must not show traces of lubricants;

otherwise, check the driven pulley unit seals.N.B.UPON RUNNING-IN, THE MASSES MUST EXHIBIT A CEN-TRAL FAYING SURFACE AND MUST NOT BE DIFFERENTFROM ONE ANOTHER.VARIOUS CONDITIONS CAN CAUSE THE CLUTCH TOTEAR.CAUTIONDO NOT OPEN THE MASSES USING TOOLS TO PREVENTA VARIATION IN THE RETURN SPRING LOAD.

CharacteristicCheck minimum thickness1 mm

Pin retaining collar

- Simultaneously turn and pull the collar manually

to remove it.N.B.USE TWO SCREWDRIVERS IF YOU HAVE ANY DIFFICUL-TY.N.B.BE CAREFUL NOT TO PUSH THE SCREWDRIVERS IN TOOFAR TO AVOID DAMAGE THAT COULD COMPROMISETHE O-RING SEAL.

- Remove the 4 torque server pins and pull the

pulley halves apart.


ENG - 97

Removing the driven half-pulley bearing

- Check there are no signs of wear and/or noisi-

ness; - Replace with a new one if there are.

- Remove the retainer ring using two flat blade

screwdrivers.

- Support the pulley bushing adequately from the

threaded side using a wooden surface.

- Using a hammer and pin, knock the ball bearing

out as shown in the figure.

- Support the pulley properly using the bell as

shown in the figure.

Specific tooling001467Y035 Bearing housing, out ø 47 mm

- Remove the roller bearing using the modular punch.


020456Y Ø 24 mm adaptor

020363Y 20-mm guide

Inspecting the driven fixed half-pulley

Version 250

- Measure the outside diameter of the pulley bush-

ing.

- Check the faying surface with the belt to make

sure there are no flaws.

- Check the riveted joints are functional.

- Check the evenness of the belt contact surface.

CharacteristicHalf-pulley minimum diameterMinimum admissible diameter: Ø 40.96 mm


ENG - 98

Half-pulley standard diameterStandard diameter: Ø 40.985 mm

Wear limit0.3 mm

Inspecting the driven sliding half-pulley

- Remove the two seal rings and the two O-rings.

- Measure the movable half-pulley bushing inside

diameter.

- Check the faying surface with the belt to make

sure there are no flaws.

- Check the riveted joints are functional.

- Check the evenness of the belt contact surface.

MOVABLE DRIVEN HALF-PULLEY DIMENSIONSSpecification Desc./Quantity

Wear limit 0.3 mmstandard diameter Ø 41.000 - 41.035 mm

maximum allowable diameter Ø 41.08 mm


ENG - 99

Refitting the driven half-pulley bearing

- Support the pulley bushing adequately from the

threaded side using a wooden surface.

- Fit a new roller bearing as shown in the figure.

- For the fitting of the new ball bearing, follow the

example in the figure using a modular punch.

Fit the retainer ringWARNINGN.B.FIT THE BALL BEARING WITH THE VISIBLE SHIELDING



020424Y Driven pulley roller casing fittingpunch

Refitting the driven pulley

- Insert the new oil seals and O-rings on the mov-

able half-pulley.

- Lightly grease the O-rings «A» shown in the fig-

ure.

- Fit the half-pulley over the bushing using the spe-

cific tool.

- Check that the pins are not worn and proceed to

refitting them in their slots.

- Refit the torque server closure collar.

- Using a curved-spout grease gun, lubricate the

driven pulley unit with approximately 6 grams of

grease. Apply grease through one of the holes in

the bushing until it comes out through the hole on

the opposite side. This operation is necessary to

avoid the presence of grease beyond the O-rings.N.B.


ENG - 100

THE TORQUE SERVER CAN BE GREASED WHETHERWITH BEARINGS FITTED OR WHEN THEY ARE BEING RE-PLACED; UNDERTAKING THE OPERATION WHEN THEBEARINGS ARE BEING SERVICED MIGHT BE EASIER.

Specific tooling020263Y Driven pulley assembly sheath

Recommended productsAGIP GREASE SM 2 Grease for the C-ring ofthe tone wheelSoap-based lithium grease containing NLGI 2 Mo-

lybdenum disulphide; ISO-L-XBCHB2, DIN

KF2K-20

Inspecting the clutch spring

- Measure the length of the spring when it is re-

laxed.

CharacteristicStandard length145 mm

Acceptable limit after use140 mm

Refitting the clutch

- Support the driven pulley spring compressor spe-

cific tool with the control screw in vertical axis.

- Arrange the tool with the medium length pins

screwed in position "C" on the inside.

- Introduce the adapter ring No. 11 with the cham-

fering facing upwards.

- Insert the clutch on the adapter ring.

- Lubricate the end of the spring that abuts against

the torque server closing collar.

- Insert the spring with its plastic holder in contact

with the clutch.

- Insert the drive belt into the pulley unit according

to their direction of rotation.

- Insert the pulley unit with the belt into the tool.

- Slightly preload the spring.


ENG - 101

- Make sure that the clutch is perfectly inserted into

the adapter ring before proceeding to tighten the

clutch nut.

- Place the tool in the clamp with the control screw

on the horizontal axis.

- Fully preload the spring.

- Apply the clutch fixing nut and tighten it to the

prescribed torque using the special 46x55 wrench.

- Loosen the tool clamp and insert the belt accord-

ing to its direction of rotation.

- Lock the driven pulley again using the specific

tool.

- Preload the clutch return spring with a traction/

rotation combined action and place the belt in the

smaller diameter rolling position.

- Remove the driven pulley /belt unit from the tool.N.B.DURING THE SPRING PRELOADING PHASE, BE CARE-FUL NOT TO DAMAGE THE PLASTIC SPRING STOP ANDTHE BUSHING THREADING.N.B.FOR DESIGN REASONS, THE NUT IS SLIGHTLY ASYM-METRIC; THE FLATTEST SURFACE SHOULD BE MOUN-TED IN CONTACT WITH THE CLUTCH.

Specific tooling020444Y Tool for fitting/ removing the drivenpulley clutch

020444Y011 adapter ring

020444Y009 wrench 46 x 55

Locking torques (N*m)Clutch unit nut on driven pulley 45 to 50


ENG - 102

Refitting the driven pulley

- Fit the clutch housing on the driven pulley paying

attention to the position of the washer indicated.

Drive-belt

- Make sure the drive belt is not damaged and does not show abnormal wear.

- Replace as indicated in the scheduled maintenance table.

Removing the driving pulley

- Turn the crankshaft until the ropes of the pulley

are on a horizontal axis


ENG - 103

- Insert the adaptor sleeve of the appropriate tool

in the hole shown in the picture

- Insert the tool in the hollows and apply the reten-

tion ring

- Bring in the ring's clamping screws while keeping

the tool to support the pulley

- Remove the fixing nut and the washer

- Remove the stationary drive pulley half.

Specific tooling020626Y008 Driving pulley lock wrench

- Remove nut «1», Belleville spring «2», and wash-

er «3».

- Remove the stationary driving half-pulley.


ENG - 104

- Detach the drive belt from the crankshaft, remove

the sliding bushing and the entire roller housing.

Inspecting the rollers case

- Check that the internal bushing shown in the fig-

ure is not abnormally worn and measure inner

diameter A.

- Measure outer diameter B of the pulley sliding

bushing shown in the figure.

- Check that the rollers are not damaged or worn.

- Check the guide shoes for the variator back-plate

are not worn.

- Check the wear of the roller housings and of the

belt faying surfaces on both pulley halves.

- Check that stationary driving pulley does not

show signs of abnormal wear on the grooved edge

and on the surface in contact with the belt.

- Check that the O-ring is not pushed out of shape.CAUTIONDO NOT LUBRICATE OR CLEAN SINTERED BUSHINGS

Characteristicmovable driving half-pulley bushing: StandardDiameter26.000 - 26.021 mm

movable driving half-pulley bushing: Maxi-mum allowable diameterØ 26.12 mm

Sliding bushing: Standard DiameterØ 25.959 ÷ 25.98 mm

Sliding bushing: Minimum admissible diame-terØ 25.95 mm

Roller: Standard diameter


ENG - 105

Ø 19.5 - 20.1 mm

Roller: Minimum admissible weight5.4 ± 0.15 g

Refitting the driving pulley

- Preassemble the movable half-pulley with the

roller contrast plate by putting the rollers in their

housings with the larger support surface touching

the pulley according to the direction of rotation.

- Check that the roller contact plate does not have

flaws and is not damaged on the grooved edge.

- Mount the complete bushing unit on the crank-

shaft.

- Fit the driven pulley/Clutch/belt unit on the en-

gine.


ENG - 106

- Fit the steel shim in contact with the bushing and

the stationary drive pulley.

- Install the appropriate tool as described in the re-

moval phase.

-Tighten the nut with washer to the prescribed tor-

que.

Specific tooling020626Y008 Driving pulley lock wrench

Locking torques (N*m)Drive pulley nut 75 - 83

Refitting the transmission cover

- Check that there are two alignment dowels and

that the sealing gasket for the oil sump on the

transmission cover is adequately fitted.

- Refit the cover and tighten the «12» screws to the

specified torque.

- Refit the steel washer and the driven pulley nut.

- Tighten the nut to the prescribed torque using the

lock wrench and the torque wrench tools.

- Refit the plastic cover.

Specific tooling020423Y Driven pulley lock wrench

Locking torques (N*m)Transmission cover screws 11 to 13 Driven pul-ley shaft nut 54 ÷ 60

End gear


ENG - 107

Removing the hub cover

- Empty the reduction oil through the drain screw

«1».

- Undo the six screws «2», and the screw «3».

- Remove gasket «4» and make sure that align-

ment dowels «5» are adequately positioned.

Removing the wheel axle

- Remove the wheel axis complete with gear.

- Remove the intermediate gear.


ENG - 108

Removing the hub bearings

- Check the state of the bearings being examined

(wear, clearance and noisiness). If faults are de-

tected, do the following.

- Use the specific bearing extractor to remove the

three 15 mm bearings (2 in the crankcase and 1 in

the hub cover).

Specific tooling001467Y013 Calliper to extract ø 15-mm bear-ings

Removing the wheel axle bearings

- Take out the clip on the outside of the hub cover.

- Support the hub cover and expel the bearing.

By means of the appropriate tools, remove the oil

seal as in the figure.


020477Y 37 mm adaptor

020483Y 30-mm guide


020489Y Hub cover support stud bolt kit


ENG - 109

Removing the driven pulley shaft bearing

- Extract the driven pulley shaft from its bearing.

- Remove the oil seal using a screwdriver and be

careful not to damage the seat.

- Remove the Seeger ring indicated.



020363Y 20-mm guide

- Remove the driven pulley shaft bearing using the

modular punch.



020363Y 20-mm guide

Inspecting the hub shaft

- Check that the 3 shafts exhibit no wear or defor-

mation on the grooved surfaces, at the bearings

and at the oil seals.

- In case of faults, replace the damaged parts.


ENG - 110

CharacteristicConnection diameter for countershaft:

A = Ø 15 - 0.01 -0.02 mm

Connection diameter for wheel shaft:

B = Ø 25 - 0.020 -0.035 mm

C = diameter 15 - 0.01 -0.02 mmBearing diameter for driven pulley shaft:

D = Ø 15 - 0.01 -0.02 mm

E = 19.8 ± 0.1F = Ø 20 - 0.01 -0.02 mm

Inspecting the hub cover

- Check that the fitting surface is not dented or distorted.

- Check the bearing bearings.

- In case of faults, replace the damaged components.


ENG - 111

Refitting the wheel axle bearing

- Support the hub cover on a wooden surface.

- Heat the crankcase cover with the specific heat

gun.

- Fit the wheel shaft bearing with a modular punch


- Fit the Seeger ring.

- Fit the oil seal with seal lip towards the inside of

the hub and place it flush with the internal surface

by means of the appropriate tool used from the 52-

mm side.

The 52-mm side of the adapter must be turned to-

wards the bearing.



020483Y 30-mm guide


ENG - 112

Refitting the hub cover bearings

In order to fit the hub box bearings, the engine

crankcase and the cover must be heated with the

special heat gun.

- The three 15-mm bearings must be fitted using

the appropriate tools:

- The 42-mm side of the adapter must be turned

towards the bearing.

Specific tooling020150Y Air heater mounting

020151Y Air heater



020412Y 15-mm guide

N.B.

TO FIT THE BEARING ON THE COVER, ADEQUATELY SUPPORT THE COVER WITH THE STUDBOLT KIT.

- Refit the driven pulley shaft bearing with a mod-

ular punch as shown in the figure.N.B.IF THE BEARING HAS AN ASYMMETRICAL BALL RETAIN-ER, PLACE IT SO THAT THE BALLS ARE VISIBLE FROMTHE HUB INNER SIDE.



020363Y 20-mm guideN.B.

WHEN FITTING THE BEARINGS ON THE ENGINE CRANKCASE, SUPPORT THE CRANKCASEPREFERABLY ON A SURFACE TO ALLOW THE BEARINGS TO BE DRIVEN VERTICALLY.

- Refit the Seeger ring with the opening facing the bearing and fit a new oil seal flush with the crankcase

from the pulley side.


ENG - 113

Refitting the hub bearings

- Install the three shafts in the engine crankcase


Refitting the ub cover

- Fit a new gasket together with the alignment

dowels.

- Seal the gasket of the breather pipe using black

silicone sealant.

- Fit the gearbox cover, making sure the breather

pipe is in the correct position.

- Position the shorter screw that can also be rec-

ognised from the different colour as shown in the

figure.

- Fix the breather tube support by means of the

lower screw.

- Fit the remaining screws and tighten the seven

screws to the prescribed torque.

Locking torques (N*m)Hub cover fixing screws 24 to 27 Hub oil drainscrews 15 to 17

Flywheel cover


ENG - 114

Removing the hub cover

- Remove the clamp fastening the pipe to the cyl-

inder, undo the two screws fixing it to the engine

and remove the electric pump together with its

support.

- Remove the seven screws fixing the flywheel

cover.

- Remove the flywheel cover.

- Remove the gasket and be careful with the two

alignment dowels.


ENG - 115

Removing the stator

- Remove the two pickup screws and the screw

holding the wiring support and the three stator

clamping screws shown in the figure.

- Remove the stator and its wiring.

Refitting the stator

- Refit the stator and flywheel carrying out the re-

moval procedure in reverse, tightening the retain-

ers to the specified torque.

Locking torques (N*m)Stator fixing screws 8 to 10 Pickup fixingscrews 3 to 4

Refitting the flywheel cover

- Fit the gasket and be careful with the two align-

ment dowels.


ENG - 116

- Fit the entire flywheel cover.

- Undo the seven screws fixing the flywheel cover,

observing the position of the plate indicated.

- Fasten the electric pump together with its support

with the two screws indicated and fasten the pipes

to the cylinder.

Locking torques (N*m)Transmission cover screw 11 to 13

Flywheel and starting

Removing the starter motor

- Remove the two screws indicated in the figure

- Take the starter motor out of its seat


ENG - 117

Removing the flywheel magneto

- Remove the screw and the plate of the starting

sprocket.

- Fit the specific tool, screw the guide bushing to

the flywheel, insert the flywheel stop tool as shown

in the picture.

Specific tooling020627Y Flywheel lock wrench

- Undo the flywheel screw and remove the washer.

- Manually screw the nut without washer, being

careful not to leave the first threads uncovered.CAUTION

SCREWING UP THE NUT WITHOUT WASHER HELPS PRO-TECT THE THREAD AGAINST THE STRAIN EXERTED BYTHE EXTRACTOR AND ALSO PREVENTS DROPPING THEFLYWHEEL ACCIDENTALLY UPON EXTRACTING IT. PO-TENTIAL DROPS MAY DAMAGE THE CERAMIC INSERTS.


ENG - 118

- Insert the extractor.

Specific tooling020467Y Flywheel extractor

- Act on the extractor to remove the flywheel to-

gether with the starting sprocket.

Inspecting the flywheel components

- Check the integrity of the internal plastic parts of the flywheel and the Pick-up control plate.

Starter gear rim

See alsoRemoving the flywheel magneto

Intermediate gear

- Remove the flywheel cover.

- Remove the intermediate gear and take it out of

its housing.

Refitting the free wheel

- Make sure the freewheel faying surfaces are in good condition.

- Thoroughly clean the free wheel to remove LOCTITE residue.


ENG - 119

- Degrease the threading of the holes in the free wheel and the clamping screws.

- Apply the recommended product to the end of the screws.

Recommended productsLoctite 243 Medium strength threadlock

Medium Loctite 243 threadlock

- Fit the freewheel on the magneto flywheel making

sure that the ground side is in contact with the fly-

wheel itself, i.e. with wheel Seeger ring visible.

- Lock the six clamping screws in criss-cross fash-

ion to the prescribed torque.

Locking torques (N*m)Screw fixing freewheel to flywheel 13 - 15

- Oil the free wheel "rollers".

Refitting the flywheel magneto

- Remove the freewheel retaining plate indicated

in the picture

- Remove the transmission gear and the freewheel


ENG - 120

- Insert the free wheel on the flywheel as shown in

the picture

- Then refit the flywheel with free wheel and trans-

mission gear

- Using the special flywheel lock wrench, tighten

up the flywheel fixing nut to the prescribed torque

- Refit the retention plate

Specific tooling020627Y Flywheel lock wrench

Locking torques (N*m)Flywheel nut 94 - 102

Refitting the starter motor

- Fit a new O-ring on the starter motor and lubricate

it.

- Fit the starter motor on the crankcase and lock

the 2 screws to the prescribed torque.

Locking torques (N*m)Starter screws 11 to 13

Cylinder assy. and timing system


ENG - 121

Removing the intake manifold

- Undo the three screws with an anti-tampering

device.

Removing the rocker-arms cover

- Remove the five screws shown in the figure.

- Remove the entire head cover.

Removing the timing system drive

- Remove the oil pump control gear and the pinion

separation washer as described in the «Engine/

Lubrication/Oil pump» section.

- Undo the central screw and collect the washer.

Undo the two fixing screws to the cylinder and re-

move the tensioner together with the gasket.


ENG - 122

- Undo the two screws indicated.

- Detach the timing chain and remove the camshaft

control pulley and the corresponding washer.

- Remove the screws indicated in the figure, the

spacer bar and the tensioner slider.

- Remove the control sprocket wheel and the tim-

ing chain.

- As regards the chain guide slider, it may only be

removed after the head has been removed.N.B.IT IS ADVISABLE TO MARK THE CHAIN IN ORDER TO EN-SURE THAT THE INITIAL DIRECTION OF ROTATION ISMAINTAINED.

Removing the cam shaft

- Undo the two indicated fixing screws to the cyl-

inder and remove the fixing plate.


ENG - 123

- Remove the camshaft.

- Acting on flywheel-side holes, push and slide off

the rocking lever pins.N.B.IF NEEDED, THE HEAD MAY BE REMOVED WITH THECAMSHAFT, ROCKER PINS AND FIXING BRACKET. THEHEAD CAN ALSO BE REMOVED WITHOUT REMOVINGTHE CHAIN AND THE CRANKSHAFT CHAIN TENSIONER.

Removing the cylinder head

- Undo the two screws «1» fixing the head to the

transmission-side crankcase half.

- Unscrew the four nuts «2» by loosening them in

two or three stages and in a crossed sequence.


ENG - 124

- Remove the head.N.B.IF NEEDED, THE HEAD MAY BE REMOVED WITH THECAMSHAFT, ROCKER PINS AND FIXING BRACKET. THEHEAD CAN ALSO BE REMOVED WITHOUT REMOVINGTHE CHAIN AND THE CRANKSHAFT CHAIN TENSIONER.

- Remove the gasket.

Removing the valvesN.B.

CHECK RESIDUAL STROKE IN ORDER TO AVOID RESONANCES IN THE INTAKE VALVES ASDESCRIBED IN THE PAGE ON «ENGINE/THERMAL GROUP AND TIMING SYSTEM/VALVECHECK» EVERY TIME THAT EITHER THE INTAKE VALVES OR THEIR COMPONENTS ARE RE-MOVED.

- Use the specific tool to remove the cotters, cap

and spring.CAUTIONREPLACE THE VALVES IN SUCH A WAY AS TO RECOG-NISE THEIR ORIGINAL POSITION ON THE HEAD.

Specific tooling020382Y011 adapter for valve removal tool

020382Y Tool to extract valve cotters


ENG - 125

- Use the specific tool to remove the valve oil seal.

Specific tooling020306Y Punch for assembling valve sealrings

- Slide off the valve and remove the lower support.

Specific tooling020382Y Tool to extract valve cotters


ENG - 126

- Remove the calibrated washer and replace, if re-

quired, as indicated above for checking residual

stroke as described in the page on «Engine/Ther-

mal group and timing system/valve check».

See alsoInspecting the valves

Removing the cylinder - piston assy.

- Remove the chain guide slider; be careful with

the two alignment dowels and remove the cylinder.

- Remove the base gasket; be careful with the two

centring dowels and the dowel pin.

- Remove the sealing rings, the pin and remove

the piston.CAUTIONTO PREVENT DAMAGING THE PISTON, SUPPORT ITWHILE REMOVING THE CYLINDER.N.B.BE CAREFUL NOT TO DAMAGE THE SEALING RINGSDURING REMOVAL.


ENG - 127

Inspecting the small endN.B.

TO MEASURE WEAR LIMITS AND COUPLING CLEARANCES, SEE THE SPECIFICATIONS CHAP-TER.

See alsoCrankcase - crankshaft - connecting rod

Inspecting the wrist pinN.B.


See alsoCylinder - piston assy.

Inspecting the pistonN.B.


See alsoCylinder - piston assy.

Inspecting the piston ringsN.B.


See alsoPiston rings

Removing the piston

- Install piston and wrist pin onto the connecting

rod, aligning the piston arrow the arrow facing to-

wards the exhaust.


ENG - 128

- Fit the wrist pin retainer ring onto the appropriate

tool

- With opening in the position indicated on the tool

S = left

D= right

- Place the wrist pin retainer ring into position using

a punch

- Fit the wrist pin retainer ring using the plug as

shown in the figureN.B.THE TOOL FOR INSTALLING THE RETAINER RINGS MUSTBE USED MANUALLY.CAUTIONUSING A HAMMER MIGHT DAMAGE THE STOPS' HOUS-ING.

Specific tooling020430Y Pin lock fitting tool

Choosing the gasket

- Provisionally fit the piston into the cylinder, without any base gasket.

- Install a dial gauge on the special tool using the short union, as shown in the figure.

Specific tooling020475Y Piston position checking tool

- Using an abutment plane, reset the dial gauge

with a preload of a few millimetres.

- Finally fix the dial gauge.

- Check the perfect sliding of the feeler pin.

- Install the tool on the cylinder without changing

the dial gauge position.

- Lock the tool using the original head fixing nuts.

- Rotate the crankshaft up to the TDC (the inver-

sion point of the dial gauge rotation)

- Measure the deviation from the reset value.


ENG - 129

- By means of the table, see the Specifications chapter identify the cylinder base gasket thickness to

be used for refitting. Correctly identify the cylinder base gasket thickness to keep the correct compres-

sion ratio.

- Remove the special tool and the cylinder.N.B.

IF DEVIATIONS (OR RECESSES OR PROJECTIONS) CLOSE TO THE CHANGE OF CATEGORYARE MEASURED, REPEAT THE MEASUREMENT AT THE OPPOSED SIDE. TO DO SO, REPEATTHE TOOL INSTALLATION BY INVERTING ITS POSITION.

See alsoSlot packing system

Refitting the piston rings

- Pistons (like cylinders) are supplied in 4 catego-

ries: A, B, C and D, and must be fitted so that the

reference arrow faces the exhaust duct. The letter

is found at the centre of the piston.

- Fit the sealing rings with the word TOP or the

identification letter facing upwards. In any case,

the tapered side of the ring must be facing oppo-

site the piston crown.

- Sealing rings are manufactured with a cylinder

contact conical cross-section and piston gaps

must be offset by 120° in order to obtain a better

bedding.

- Lubricate rings with engine oil when fitting them.


ENG - 130

Refitting the cylinderN.B.

BEFORE FITTING THE CYLINDER, CAREFULLY BLOW OUT THE LUBRICATION DUCT AND OILTHE CYLINDER LINER.

- Check the position of the centring dowels and

dowel pin and fit a gasket with a thickness previ-

ously determined.

- Using the specific tool fit the cylinder paying at-

tention that the chain does not remain in the timing

system compartment.

Specific tooling020426Y Piston fitting fork

020393Y Piston assembly band

Inspecting the cylinder headN.B.


See alsoCylinder Head


ENG - 131

Inspecting the timing system components

- Check that the guide slider and the tensioner

slider are not worn out.

- Ensure that the camshaft control pulley chain as-

sembly and the sprocket wheel are not worn.

- If you detect wear, replace the parts or, if the

chain, sprocket wheel and pulley are worn, replace

the whole unit.

- Remove the centre screw with the washer and

the tensioner spring. Check that the one-way

mechanism is not worn.

- Check the condition of the tensioner spring.

- If examples of wear are found, replace the whole

unit.

Inspecting the valve sealingsN.B.



Inspecting the valvesN.B.THE RESIDUAL STROKE OF THE INTAKE SPRINGS MUSTRANGE BETWEEN 0.8 - 1.8 MM SO THAT THERE ARE NORESONANCES. TO SOLVE THIS, THE SPRING IS SHIM-MED WITH CALIBRATED WASHERS: 0.4 - 0.8 - 1.2 MM


ENG - 132

RESIDUAL STROKE CHECK

Follow these steps to check the residual stroke:

- Fit the specific tool on the head and fasten the

dial gauge

Specific tooling020688Y Dial gauge support

- Check that the dial gauge is adequately posi-

tioned, that is as parallel as possible to the valve

axis, and the cap must be within the level area.

- Turn the crankshaft until the Intake valves are at their maximum lift.N.B.

USING A DIAL GAUGE IDENTIFY THE MAXIMUM LIFT AND LOCATE THE EXACT POINT ATWHICH THE NEEDLE STARTS TURNING IN THE OPPOSITE SENSE.

- Reset the dial gauge.


ENG - 133

- Unscrew the stop nut of the set screw.

- Using the dial gauge measure the residual stroke

value by undoing the set screw until the end of

stroke.

CharacteristicResidual stroke:0.8 - 1.8 mm

- Check residual stroke by comparing it with the data contained in the next page.

RESIDUAL STROKE CHECK

- Check the residual stroke and afterwards make sure that it falls within the predetermined limits.

CharacteristicResidual stroke:

0.8 - 1.8 mm

RESIDUAL STROKE OVER 1.7 mm

- Replace the calibrated washer with a thicker one

so that it is within the residual stroke values.

RESIDUAL STROKE SMALLER THAN 0.9 mm

- Replace the calibrated washer with a thinner one

so that it is within the residual stroke values. -

USE LIMITS

- Replace the head if values exceed the use limits

of the residual stroke.CAUTIONCHECK BOTH INTAKE VALVES.ADJUST EACH TIME A VALVE OR ANY COMPONENT OFTHE VALVE RETURN MECHANISM HAS TO BE RE-PLACED.WHEN THE CALIBRATED WASHER IS REPLACED, THEVALVE SEAL RING MUST BE REPLACED AS WELL.WHEN A NEW HEAD OR VALVE IS FITTED, THE 0.8-mmWASHER HAS TO BE CHECKED.


ENG - 134

NEVER INSERT MORE THAN ONE WASHER IN THE SAMESEAT.

CharacteristicResidual stroke:0.8 - 1.8 mm

- Refer to the «Engine / Thermal group and timing system / Valve removal» page to see the re-

placement steps

See alsoRemoving the valves

N.B.



Inspecting the springs and half-cones

- Check that the upper and lower supporting spring

washers, the cotters and the oil seal show exhibit

no signs of abnormal wear. Replace a component

when worn.

N.B.



Refitting the valves

- Lubricate the valve guides with engine oil.

- Place the valve spring supports on the head.

- Using the special punch, fit the four valve seal

rings.

- Fit the valves, the springs and the spring retaining

caps. Using the appropriate tool with adapter,

compress the springs and insert the cotters in their

seats.


ENG - 135

N.B.DO NOT CHANGE THE VALVE FITTING POSITION. FIT THEVALVE SPRINGS WITH THE REFERENCE COLOUR ONCOTTER SIDE (TURNS WITH GREATER PITCH).

Specific tooling020306Y Punch for assembling valve sealrings

020382Y011 adapter for valve removal tool

020382Y Tool to extract valve cotters

Inspecting the cam shaftN.B.



Refitting the head and timing system components

Assemble the timing chain sprocket wheel on the

crankshaft with the chamfering facing the insertion

side and observing the position of the reference

dowel.

- Loop the timing control chain «1» around the

crankshaft.

- Fit the guide slider and the tensioner pad «2» on

the head side.

- Fit spacer «5» with fixing screw «6».

- Tighten the screws to the prescribed torque.

Locking torques (N*m)Slider screw 10 - 14 Nm


ENG - 136

- Fit the head gasket and check that the alignment

dowels work properly.

- Insert the head.

- Lubricate the stud bolt threads with engine oil.

- Tighten up the nuts to an initial pre-torque of 7±1

Nm.

- Tighten up the nuts to a second pre-torque of 10

±1 Nm

- To carry out the operations described above, fol-

low the tightening sequence in the figure.

- Fit the two screws on the outside of the timing

chain side and tighten them to the specified torque.N.B.BEFORE INSTALLING THE HEAD, MAKE SURE THAT THELUBRICATION CHANNEL IS CLEAN USING A COM-PRESSED AIR JET.

Locking torques (N*m)Timing chain tensioner support screw 11 to 13

Fit the pins and rocking levers.

- Lubricate the two rocking levers through the

holes at the top.

- Lubricate the 2 bearings and insert the camshaft

in the cylinder head with the cams corresponding

to the rocking levers.

- Insert the retention plate and tighten the two

screws shown in the figure to the prescribed tor-

que.

Locking torques (N*m)Plate screws 4 - 6 Nm

Insert the spacer on the cam shaft.

- Rotate the engine so that the piston is at top dead

centre, using the reference marks on the flywheel

and the crankcase.

- Insert the pulley on the camshaft while keeping

the reference 4V in correspondence with the ref-

erence mark on the head.

- Holding this position insert the chain on the cam-

shaft control pulley.

- Lock the fixing screws.


ENG - 137

Locking torques (N*m)Counterweight screw 7 to 8.5

Set the tensioner cursor to the rest position.

- Fit the chain tensioner on the cylinder, using a

new gasket, and tight the two screws to the pre-

scribed torque.

Insert the chain tensioning screw, together with the

spring and washer, tightening it to the prescribed

torque.

Locking torques (N*m)Tensioner screws 11 to 13 Tensioner cover 5 - 6Nm

- Check valve clearance.

CharacteristicValve clearance

Intake: 0.10 mm Exhaust: 0.15 mm

Refitting the rocker-arms cover

- Refit the cylinder head cover and tighten the 5

clamping screws to the prescribed torque.

- Make sure the gasket is positioned properly.

Locking torques (N*m)Tappet cover screws 5 - 6 Nm


ENG - 138

Refitting the intake manifold

- Fit the intake manifold and do up the three

screws.

Locking torques (N*m)Intake manifold screws 11 to 13

Crankcase - crankshaft

Splitting the crankcase halves

AXIAL CLEARANCE CHECK

- Before opening the engine crankcase, it is ad-

visable to check the axial clearance of the crank-

shaft. Use a specific tool to check axial clearance.

- Higher clearances are signs of wear on the crank-

shaft - crankcase supporting surfaces.

Specific tooling020262Y Crankcase splitting plate


CharacteristicAxial crankshaft/crankcase clearance: Stand-ard clearance0.15 - 0.40 mm (when cold)

Axial connecting rod - crankshaft clearanceStandard clearance0.20 to 0.50 mm

CRANKCASE OPENING

- Undo the ten crankshaft coupling screws.

- Separate the crankcase halves while keeping the

crankshaft in one of these two halves.

- Only after the halves have been separated, can

the crankshaft be checked.CAUTIONWHILE OPENING THE CRANKCASES AND REMOVINGTHE CRANKSHAFT, CHECK THAT THE THREADEDSHAFT ENDS DO NOT INTERFERE WITH THE MAIN BUSH-


ENG - 139

INGS. FAILURE TO OBSERVE THIS PRECAUTION CANDAMAGE THE MAIN BUSHINGS.CAUTIONKEEP THE CRANKSHAFT IN ONE OF THE TWO HALVESOF THE CRANKCASE WHEN SEPARATING IT. IF YOU FAILTO DO THIS, THE CRANKSHAFT MIGHT ACCIDENTALLYFALL.

- Remove the crankcase halves gasket and be

careful with the two alignment dowels.

- Unscrew the oil filter fitting if required.


ENG - 140

- Once the crankcase halves have been separa-

ted, reach and remove the internal bulkhead and

the protection bulkhead for the mesh pre-filter.

Inspecting the crankshaft componentsN.B.



Inspecting the crankshaft alignmentN.B.



Inspecting the crankcase halves

- Before proceeding to check the crankcase

halves, thoroughly clean all surfaces and oil ducts.

- On the transmission-side crankcase half, take

particular care when handling the oil pump com-

partment and the oil ducts, the by-pass duct, the

main bushings and the cooling jet on the trans-

mission side (see diagram).

- Take particular care, also, that there are no signs

wear in the oil by-pass valve housing (see Chapter

Lubrication), as this could prevent a good seal in

the piston, which regulates the oil pressure.

- On the flywheel side crankcase half, take partic-

ular care cleaning the oil ducts for the main bush-

ings, the oil duct for the jet that lubricates the


ENG - 141

cylinder head and the oil drainage duct at the fly-

wheel side oil seal.

- Inspect the coupling surfaces on the crankcase

halves for scratches or deformation, taking partic-

ular care with the cylinder/crankcase surfaces and

the crankcase halves surfaces.

- Defects in the crankcase coupling gasket be-

tween the crankcase halves or the mating surfaces

shown in the diagram, could cause a drop in the

oil pressure lubricating the main bushings and

connecting rod.

- Check the main bearing seats that limit axial

clearance in the crankshaft show no signs of wear.

The dimension between these seats is measured

by way of the procedure described previously for

measuring the crankshaft axial clearance and di-

mensions.N.B.THE JET IS FED THROUGH THE MAIN BUSHINGS. PROP-ER OPERATION OF THIS COMPONENT IMPROVES PIS-TON CROWN COOLING. CLOGGING HAS EFFECTS THATARE DIFFICULT TO DETECT (PISTON TEMPERATURE IN-CREASE). FAILURE OR LEAKS CAN CAUSE A CONSID-ERABLE DROP IN THE LUBRICATION PRESSURE FORMAIN BUSHINGS AND CONNECTING ROD.N.B.THE HEAD LUBRICATION CHANNEL IS PROVIDED WITHA SHUTTER JET; THIS GIVES A "LOW PRESSURE" HEADLUBRICATION; THIS CHOICE WAS MADE TO REDUCETHE OIL TEMPERATURE IN THE SUMP. THE JET CLOG-GING IMPAIRS THE HEAD LUBRICATION AND THE TIM-ING MECHANISMS. A JET FAILURE CAUSES A DE-CREASE OF THE MAIN BUSHING AND CONNECTING RODLUBRICATION PRESSURE.

Inspecting the crankshaft plain bearings

- To obtain a good bushing lubrication it is neces-

sary to have both an optimal lubricating pressure

(3.2 bar) and a good oil flow rate; the bushings

must be correctly positioned so as not to obstruct

the oil supply channels.

- The main bushings are comprised of two half-

bearings, one with holes and channels for lubrica-

tion whereas the other is solid.


ENG - 142

- The solid half-bearing is intended to stand the

thrusts caused by combustion, and for this reason

it is arranged opposite the cylinder.

- To prevent shutters in the oil feeding channels,

the matching surface of the two half-bearings must

be perfectly orthogonal to the cylinder axis, as

shown in the figure.

- The oil feeding channel section is also affected by the bushings driving depth compared with the

crankshaft axial clearance of the limiting surface.N.B.



Coupling chartN.B.



Refitting the crankcase halves

- Fit the internal bulkhead and lock the two screws

to the prescribed torque.

- Fit the oil filter fitting and tighten it to the prescri-

bed torque.

- Position the oil pre-filter element as shown in the

picture.


ENG - 143

- Place a new gasket on one of the crankcase

halves, preferably on the transmission side, to-

gether with the alignment dowels.

- Lubricate the main bushings with engine oil and

insert the crankshaft in the transmission-side

crankcase half.

- Reassemble both crankcase halves.

- Fit the ten screws and tighten them to the pre-

scribed torque.

- Assemble a new O-Ring on the pre-filter and lu-

bricate it with engine oil.

- Insert the filter on the engine with the relative cap.

- Tighten to the specified torque.

Locking torques (N*m)Internal engine crankcase bulkhead (transmis-sion-side half shaft) screws 4 to 6 Engine-crank-case coupling screws 11 to 13 Oil filter on


ENG - 144

crankcase fitting 27 to 33 Engine oil drainageplug/ mesh filter 24 to 30

Studs

Check that the stud bolts have not worked loose

from their seat in the crankcase.

Check the depth of stud bolt driving with a gauge,

as indicated in the picture. If it varies significantly

from the driving depth indicated, it means that the

stud bolt has yielded.

In this case, replace it.

By working on two fitted cylinder head fixing nuts,

nut and lock nut, as shown in the picture, remove

the stud bolt from its seat.

Clean the threaded seat on the carter thoroughly.

Refit a new stud bolt and apply the special product

on the threading crankcase side.

Tighten up to the depth of the driving indicated.

Recommended productsLoctite Quick Set Loctite 270 high strengththreadlockLoctite 270 high strength threadlock

Lubrication


ENG - 145

Conceptual diagrams

The high pressure circuit is highlighted in blue. The low pressure circuit is highlighted in green

The lobe pump «1» sucks in oil from the sump through the mesh pre-filter «2», pushes it into the car-

tridge filter «3»; the main bushings and the big end are lubricated (with high pressure) through the

suitable passages found in the crankcase halves «4» whereas the piston pin and connecting rod small

end are lubricated via jet «5».

Afterwards, the oil, through a nozzle «6» whose function is to reduce the flow rate, reaches the timing

system where it lubricates the camshaft and from there, the valves and rockers «7». The oil passes

through the timing chain conduit and returns to the sump «8» by gravity

Oil pressure check

- Remove the electrical minimum oil pressure

switch connection and remove the switch.

- Check that the oil pressure reading is between

0.5 and 1.2 atm with the engine idling at 1650 rpm

and the oil at the required temperature (wait for at

least one electric ventilation).

- Check that the oil pressure is between 3.2 and

4.2 atm with the engine running at 6000 rpm and

the oil at the required temperature.


ENG - 146

- Remove the appropriate tools once the meas-

urement is complete, refit the oil pressure switch

and washer, tightening it to the specified torque

and fit the flywheel cover.

- If the oil pressure is not within the specified limits,

in the following order, check: the oil filter, the oil

by-pass valve, the oil pump and the crankshaft

seals.N.B.THE CHECK MUST BE CARRIED OUT WITH OIL AT THECORRECT LEVEL AND WITH AN OIL FILTER IN PROPERCONDITION.

CharacteristicOil pressureMinimum pressure admitted at 6000 rpm: 3.2 atm.

Locking torques (N*m)Minimum oil pressure sensor 12 to 14

Crankshaft oil seals

Removal

- Remove the transmission cover and the com-

plete drive pulley beforehand

- Install the base of the appropriate tool on the oil

seal using the screws provided.

Specific tooling020622Y Transmission-side oil seal punch


ENG - 147

- Screw the threaded bar onto the base of the tool

and extract the oil seal.


Refitting

- Always use a new oil seal upon refitting

- Prepare the new oil seal by lubricating the sealing

lip.

- Preassemble the oil seal with the appropriate tool

by positioning the screws.

- Insert the sheath over the crankshaft.

- Insert the tool with the oil seal on the crankshaft

until it comes into contact with the crankcase.

- Insert the adaptor bushing of the tool in the hole

on the crankcase.

- Orientate the oil seal by inserting the bracket

which is part of the appropriate tool.

- Tighten the threaded bar onto the crankshaft as

far as it will go.

- Use the nut to move the base of the tool until you

can see the end of the oil seal driving stroke

- Remove all the tool components following the

procedure but in reverse orderCAUTIONDO NOT LUBRICATE THE KEYING SURFACE ONTO THEENGINE CRANKCASE.CAUTIONORIENT THE OIL SEAL BY POSITIONING THE CHAINHOUSING CHANNEL FACING DOWNWARDS. WHEN THEPOSITION IS REACHED, DO NOT RETRACT THE OILSEAL. FAILURE TO COMPLY WITH THIS RULE CANCAUSE A WRONG POSITIONING OF THE OIL SEALSHEATH.CAUTIONFAILURE TO COMPLY WITH THIS ASSEMBLY PROCE-DURE CAN SERIOUSLY DAMAGE THE ENGINE DUE TOTHE WRONG TENSIONING OF THE OIL PUMP CONTROLCHAIN.


ENG - 148


Oil pump

Removal

- Undo the two clamping screws in the figure and

remove the cover over the pump control sprocket.

- Block the rotation of the oil pump control pulley

with a screwdriver inserted through one of its two

holes.

- Remove the central screw with cup washer, as

shown in the diagram.

- Remove the chain with the crown.

- Remove the control sprocket wheel with relative

O-ring.


ENG - 149

- Remove the oil pump by undoing the two screws

in the figure.

- Remove the oil pump seal.N.B.IT IS ADVISABLE TO MARK THE CHAIN IN ORDER TO EN-SURE THAT THE INITIAL DIRECTION OF ROTATION ISMAINTAINED.

Inspection

- Remove the two screws and the oil pump cover.

- Remove the circlip retaining the innermost rotor.

- Remove and wash the rotors thoroughly with pet-

rol and compressed air.

- Reassemble the rotors in the pump body, keep-

ing the two reference marks visible Replace the

retainer ring.

- Check the clearance between the rotors in the

position shown in the diagram using a feeler

gauge.

Measure the distance between the outer rotor and

the pump body (see figure).

- Check the axial clearance of the rotors using a

trued bar as shown in the figure.

CharacteristicAxial rotor clearanceLimit values admitted: 0.09 mm

Distance between the outer rotor and the pumpbodyAdmissible limit clearance: 0.20 mm

Distance between the rotorsAdmissible limit clearance: 0.12 mm


ENG - 150

Refitting

- Check there are no signs of wear on the oil pump

shaft or body.

- Check there are no signs of scoring or wear on

the oil pump cover.

- If you detect non-conforming measurements or

scoring, replace the faulty parts or the unit.

- Fit the pump cover in the position that permits the

crankcase clamping screws to be aligned.

- Make sure the gasket is positioned properly and

refit the pump on the engine crankcase. The pump

can only be fitted in one position. - Tighten the

screws to the prescribed torque.

- Fit the sprocket wheel with a new O-ring.

- Fit the chain.

- Fit the central screw and the cup washer. Tighten


-Fit the oil pump cover, by tightening the two

screws to the prescribed torque.N.B.FIT THE CUP WASHER SO THAT ITS OUTER RIM TOUCH-ES THE PULLEY. MAKE SURE THAT THE PUMP TURNSFREELY.

Locking torques (N*m)Screws fixing oil pump to the crankcase 5 to 6Oil pump command sprocket screw 10 to 14 Oilpump cover screws 0.7 - 0.9


ENG - 151

Removing the oil sump

- Drain the oil from the sump.

- Remove the seven screws indicated in the figure

and the bracket of the rear brake pipes.

- Check the correct position of the three alignment

dowels «1» and remove gasket «2», spring and

by-pass piston «3».

Inspecting the by-pass valve

- Check the unloaded spring length.

- Check that the small piston is not scored.

- Ensure that it slides freely on the crankcase and

that it guarantees a good seal.

- If not, eliminate any impurities or replace defec-

tive parts.

CharacteristicBy-pass check up: Standard length54.2 mm


ENG - 152

Refitting the oil sump

- Check the correct position of alignment dowels

«1».

- Fit a new gasket «2».

- Fit the by-pass piston and spring «3».

- Assemble the oil sump by tightening the seven

fixing screws and be careful with the plate indica-

ted.

- Tighten to the specified torque.

Locking torques (N*m)Oil sump screws 10 to 14


ENG - 153

INDEX OF TOPICS

INJECTION INJEC

MSS Nexus 125 i.e. (2008) Injection

INJEC - 155

TRANSPARENCYSpecification Desc./Quantity

1 Throttle body and electronic injection control unit (MIU)2 Fuel injector3 Instrument panel4 Injection load solenoid5 Water temperature sensor6 Fuel pump7 HV coil8 Lambda probe9 Speed sensor10 Battery 12V - 12 Ah11 Diagnostics socket connector

MIU injection system

This vehicle is fitted with an integrated injection and ignition system.

Injection is indirect in the manifold through an electro-injector.

The injection and ignition are timed on the four-stroke cycle by means of a tone wheel keyed on to the

crankshaft (24-2 teeth) and pick-up sensor.

Combustion and ignition are managed on the basis of engine revs and throttle valve opening. Further

corrections are made according to the following parameters:

- Coolant temperature.

- Intake air temperature

- Lambda probe

The system implements an idle feeding correction with cold engine through a Stepper motor on a by-

pass circuit of the throttle valve. The control unit manages the Stepper motor and the injector opening

time, thereby ensuring the idle steadiness and the proper combustion.

In all conditions of use, mixture preparation is managed by modifying the injector opening time.

The fuel system pressure is kept constant based on the ambient pressure.

The fuel system circuit consists of:

- Fuel pump

- Fuel filter

- Injector

- Pressure regulator

The pump, the filter and the regulator are placed inside the fuel tank on a single support.

The injector is connected by two pipes provided with quick couplings. This allows obtaining a continuous

circulation, thereby avoiding the risk of fuel boiling. The pressure regulator is situated at the end of the

circuit.

The fuel pump is controlled by the MIU control unit; this ensures the scooter safety

The ignition circuit consists of:

- HV coil

- HV cable

- Shielded cap

Injection MSS Nexus 125 i.e. (2008)

INJEC - 156

- MIU control unit

- Spark plug

The MIU control unit manages ignition with the best advance ensuring four-stroke timing (ignition only

in the compression phase) at the same time.

The MIU injection-ignition system controls engine functions by means of a pre-set program.

Should any input signals fail, an acceptable working order of the engine is ensured to allow the user to

reach a service station.

Of course, this cannot happen when the rpm-timing signal is missing, or when the failure involves the

control circuits:

- Fuel pump

- HV coil

- Injector

The control unit is provided with a self-diagnosis

system connected to an indicator light in the in-

strument panel.

Failures are detected and restored by the diag-

nostic tester.

In any case, when the fault is no longer present,

the data storage is automatically cleared after 16

cycles of use (cold start, running at regular engine

temperature, stop).

The diagnostic tester is also required to adjust the

idle mixture.

Specific tooling020680Y Diagnosis Tool


INJEC - 157

The MIU injection-ignition system carries out

checks on the rpm indicator and the electric fan for

radiator cooling.

The MIU control unit has a decoder for the anti-

theft immobilizer system.

The MIU control unit is connected to a diagnostic

LED on the instrument panel, that also carries out

the deterrent flashing functions.

The MIU control unit power supply is furthermore controlled by the emergency switch; that is to provide

further safety for the vehicle.

PrecautionsTroubleshooting hints

1 A MIU failure is more likely to be due to the connections than to the components.

Before troubleshooting the MIU system, carry out the following checks:

A: Electrical power supply

a. Battery voltage

b. Blown fuse

c. Remote controls

d. Connectors

B: Chassis ground

C: Fuel system

a. Broken fuel pump

b. Dirty fuel filter

D: Ignition system

a. Faulty spark plug

b. Broken coil

c. Broken shielded cap

E: Intake circuit

a. Dirty air filter

b. Dirty by-pass circuit

c. Faulty Stepper motor

F: Other

a. Incorrect distribution timing

b. Wrong idle mixture

c.Incorrect reset of the throttle valve position sensor

2 MIU system faults may be caused by loose connectors. Make sure that all connections have been

correctly made.


INJEC - 158

Check the connections as follows:

A check that the terminals are not bent.

B check that the connectors have been properly connected.

C check whether the malfunction can be fixed by shaking the connector slightly.

3 Check the entire system before replacing the MIUIf the fault is fixed by replacing the MIU control unit,

install the original control unit again and check if the fault occurs again.

4 Use a multimeter with an internal resistance of more than 10K Ohm /V when troubleshooting. Instru-

ments that are not suitable might damage the MIU central control unit. Use instruments with definitions

over 0.1V and 0.5 W , the precision must be greater than 2%.

1. Before fixing any part of the injection system, check to see if there are any registered faults. Do not

disconnect the battery before checking for faults.

2. The fuel supply system is pressurised at 250 kPa (2.5 BAR). Before disconnecting the fast-release

fitting of the fuel supply pipe, check that there are no naked flames. Do not smoke. Act with caution to

avoid spraying fuel to your eyes.

3. When fixing electric components, operate with the battery connected only when actually required.

4. When functional checks are performed, check that the battery voltage is over 12V.

5. Before any attempt to start the vehicle, check to make sure there is at least two litres of fuel in the

tank. Failure to respect this norm will damage the fuel pump.

6. If the vehicle is expected to remain unused for a long time, refill the tank up to a little over half the

level. This will ensure the pump will be covered by fuel.

7. When washing the vehicle, be careful with the electric components and cable harnesses.

8. When an ignition problem is detected, start the checks from the battery and the injection system

connections.

9. Before disconnecting the MIU ECU connector, perform the following steps in the order shown:

- Set the switch to «OFF»

- Disconnect the battery

Failure to respect this norm may damage the control unit.

10. Do not invert the poles when fitting the battery.

11. To avoid causing any damage, disconnect and reconnect the MIU system connectors only if re-

quired. Before reconnecting, check that the connectors are dry.

12. When carrying out electric inspections, do not force the tester probes into the connectors. Do not

take measurements not specifically foreseen by the manual.

13. At the end of every check performed with the diagnostic tester, remember to protect the system

connector with its cap. Failure to observe this precaution may damage the MIU control unit.

14. Before reconnecting the quick couplers of the power supply system, check that the terminals are

perfectly clean.


INJEC - 159

Terminals setup

TERMINAL LAYOUTSpecification Desc./Quantity

1 Injection telltale light2 Rpm indicator3 -4 - Lambda probe5 + battery under permanent power supply6 + Battery7 Immobilizer aerial8 Electric fan solenoid9 Water temperature sensor10 -11 + Lambda probe12 engine stop switch13 Engine speed sensor (+)14 Fuel injector15 Engine speed sensor (-)16 Diagnostics socket output17 Immobilizer LED18 Side stand short circuited on pin 1919 -20 Injection load solenoid21 -22 HV coil23 -24 Start up enabling25 -26 Ground lead

EMS circuit diagram

KEY

1. Injection ECU

7. 15A fuse

13. 7,5A fuse

14. 7.5A fuse



INJEC - 160

17. diagnostics socket

18. Coolants temperature sensor

19. stand button


21. fuel pump

22. injector

23. lambda probe

24. hv coil


26. Water pump

27. Immobilizer decoder

28. electric fan

29. electric fan remote control

30. 15A fuse

31. 15A fuse



47. starter motor

48. battery

56. instrument panel

Troubleshooting procedure

Engine does not start

ENGINE DOES NOT START IF ONLY PULLEDPossible Cause Operation

Immobiliser enabling signal System not encodedSystem not efficient, repair according to the indications of the

self-diagnosisPresence of faults detected by the self diagnosis Pump relay

HV coilInjector

Revolution timing sensorFuel system Fuel in the tank

Fuel pump activationFuel pressure (low)

Injector capacity (low)Power to the spark plug Shielded spark plug cap HV coil (secondary insulation)

Parameter reliability Coolant temperatureDistribution timing - injection ignition

Intake air temperatureEnd of compression pressure End of compression pressure


INJEC - 161

Starting difficulties

ENGINE START-UP PROBLEMSPossible Cause Operation

Presence of faults detected by the self diagnosis Pump relayHV coilInjector

Revolution timing sensorAir temperature

Coolant temperatureStart-up speed Starter motor and solenoid

BatteryGround connections

End of compression pressure End of compression pressurePower to the spark plug Spark plug

Shielded capHV coil

Speed-timing sensorIgnition advance

Fuel system Fuel pressure (low)Injector capacity (low)Injector sealing (poor)

Correctness of the parameters Coolant temperatureStepper throttle valve position intake air temperature (steps

and actual opening)Cleaning of the auxiliary air pipe and throttle valve; air filter ef-

ficiency

Engine stops at idle

ENGINE DOES NOT IDLE/ IDLING IS UNSTABLE/ IDLING TOO LOWPossible Cause Operation



Coolant temperatureIgnition efficiency Spark plug

Ignition timingCorrectness of the parameters Throttle valve position sensor

StepperCoolant temperature sensor

Intake air temperature sensorIntake system cleaning Air filter

Diffuser and throttle valveAdditional air pipe and Stepper

Intake system sealing (infiltrations) Intake manifold - headThrottle body - manifold

Intake sleeveFilter box

Fuel system (low pressure) Fuel pumpPressure regulator

Fuel filterInjector capacity

Engine does not rev down

ENGINE DOES NOT RETURN TO IDLING SPEED/IDLING SPEED TOO HIGHPossible Cause Operation

Presence of faults detected by the self diagnosis Pump relay


INJEC - 162

Possible Cause OperationHV coilInjector


Coolant temperatureIgnition efficiency Ignition timing

Correctness of the parameters Throttle valve position sensorStepper

Coolant temperature sensorIntake air temperature sensor





Exhaust backfires in deceleration

EXHAUST BACKFIRES WHEN DECELERATINGPossible Cause Operation



Coolant temperatureLambda probe

Correctness of the parameters Throttle valve position sensorStepper

Coolant temperature sensorIntake air temperature sensor





Exhaust system sealing (infiltrations) Manifold - headManifold - silencersilencer welding

Engine revs irregularly

ENGINE IRREGULAR PERFORMANCE WITH VALVE SLIGHTLY OPENPossible Cause Operation

Intake system cleaning Air filterDiffuser and throttle valve

Additional air pipe and StepperIntake system sealing Intake sleeve

Filter boxIgnition system Spark plug wear check

Parameter reliability Throttle valve position signalCoolant temperature indicator

Intake air temperature indicatorIgnition advance

TPS reset successful TPS reset successfulPresence of faults detected by the self diagnosis Pump relay

HV coil


INJEC - 163

Possible Cause OperationInjector



Poor performance at full throttle

POOR ENGINE PERFORMANCE AT FULL POWER/ ENGINE IRREGULAR PERFORM-ANCE ON PICKUP

Possible Cause OperationPresence of faults detected by the self diagnosis Pump relay

HV coilInjector



Spark plug power supply Spark plugShielded cap

HV cableHV coil

Intake system Air filterFilter box (sealing)

Intake sleeve (sealing)Parameter reliability Throttle valve position signal

Coolant temperature indicatorIntake air temperature indicator

Ignition advanceFuel system Fuel level in the tank

Fuel pressureFuel filter

Injector capacity

Engine knocking

PRESENCE OF KNOCKING (COMBUSTION SHOCKS)Possible Cause Operation




Ignition efficiency Spark plugParameter reliability Throttle valve position signal

Coolant temperature indicatorIntake air temperature indicator

Ignition advanceIntake system sealing Intake sleeve

Filter boxTPS reset successful TPS reset successful

Fuel system Fuel pressureFuel filter

Injector capacityFuel quality

Selection of the cylinder base gasket thickness Selection of the cylinder base gasket thickness


INJEC - 164

Fuel supply system

The fuel system circuit includes the electric pump, the filter, the pressure regulator, the electro-injector

and the fuel delivery pipes.

The electrical pump is located in the tank from which the fuel is pumped and sent to the injector through

the filter.

The pressure is controlled by the pressure regulator situated in the pump assembly in the tank.

Removing the butterfly valve

Remove the helmet compartment.

Remove the fuel piping clamping screw indicated

in the figure.


INJEC - 165

Remove the fast-release fittings from the injector

support.

Remove the injector connector.

Remove the three screws fixing the manifold to the

cylinder head and the clip fixing the throttle body

to the manifold.

Remove the MIU ECU connector.


INJEC - 166

Remove the clip fixing the throttle body to the air

cleaner bellows.

Remove the gas command fitting as indicated in

the picture

Refitting the butterfly valve

To refit, perform the operations in the reverse or-

der from the removal operations being careful to

position the clip fixing the throttle body to the air

filter bellows at 45° as shown in the photograph.


INJEC - 167

Pump supply circuit

INJECTION LOADSSpecification Desc./Quantity

1 Battery 12V - 12 Ah2 Fuse 10 A3 Fuse 15A4 Ignition switch contacts5 Fuse 7.5 A6 Injection load solenoid7 Fuel pump8 HV coil9 Fuel injector10 Lambda probe11 Electric fan solenoid

When switched to "ON", the fuel pump starts to rotate for two seconds and then stops. When the engine

starts, in the presence of rpm timing signal the pump is continuously supplied.

ELECTRICAL DATA

• Pump winding resistance ~ 1.5 Ohm

• Input current during normal functioning 1.4 to 1.8 A

• Input current to the closed hydraulic circuit ~ 2 A (to be checked with specific tool for fuel

pressure control, choking the circuit on the return pipe)


INJEC - 168

Check the efficiency of 10 A fuse No. 2 injection

load.

Check the efficiency of 7,5 A fuse No. 11 key-con-

trolled control unit power supply.

Check the efficiency of the injection load solenoid.

Check the resistance of the energising coil be-

tween pins 86 and 85: 40 to 80 Ohm

Apply a voltage of 12V to pins 86 and 85; make

sure that there is continuity between pins 30 and

87 of the solenoid.


INJEC - 169

Check the power supply line of the injection load

remote control energising coil: After switching to

"ON", make sure there is battery voltage, for two

seconds, between the black/white cable and

black-violet cable of the remote control base. If

there is not, check the continuity of the black/white

cable between fuse block and the remote control

base and of the black/violet cable between pin 20

of the control unit and the remote control base.N.B.CONTINUITY TESTS MUST BE CARRIED OUT WITH THECOMPONENTS DISCONNECTED. (SOLENOIDS, CON-TROL UNIT, FUSES ETC.).


INJEC - 170

Check the presence of fixed voltage between the

red/blue cable of the remote control base and

earth. If not, check the continuity of the red/blue

cable between the fuse box (No. 2 10 A) and the

remote control base.N.B.CONTINUITY TESTS MUST BE CARRIED OUT WITH THECOMPONENTS DISCONNECTED. (SOLENOIDS, CON-TROL UNIT, FUSES ETC.).


INJEC - 171

pump circuit 6

Check, on switching to "ON", that there is battery

voltage, for about two seconds, to the Black-Green

cable of the pump connector and ground with

pump connector disconnected. Otherwise, check

the continuity of the Black-Green cable between

the pump connector and the remote control base.

Check the efficiency of the ground line of the fuel

pump by measuring the continuity between the

pump connector black cable, system side, and the

ground.

If, when switching to "ON", the pump continues to

turn after two seconds of activation, check, with the

control unit disconnected and the injection load re-

mote control disconnected, that the Black-Purple

cable (pin 20 on the interface wiring) is insulated

from the ground.


Circuit leak test

Install the appropriate tool for fuel pressure control

with the pipe fitted with the pressure gauge on the

delivery pipe..


INJEC - 172

Check during regular operation by placing the ap-

propriate tool between the pump and the injector.

With the battery voltage> 12 V check that the fuel

pressure is 2.5 BAR and that the input current is

1.4 to 1.8 A

With the battery voltage > 12 V, check the pump flow rate by disconnecting from the injector the pipe

equipped with the pressure gauge of the appropriate tool. Get a graded burette with a flow rate of

approximately 1 L. Rotate the pump using the active diagnoses of the palm top computer. Using a pair

of long flat needle-nose pliers, choke the fuel pipe making the pressure stabilise at approx. 2.5 BAR.

Check that within 15 seconds the pump has a flow rate of approx. 110 cm³.

Specific tooling020480Y Petrol pressure check kit

Fuel filter check

Disconnect the terminals from the electric pump

Remove the screw shown in the picture


INJEC - 173

Remove the clip fixing the piping to the filter shown

in the picture

Separate the lower part of the pump mounting as

shown in the picture.

Remove the filter from the pump mounting


INJEC - 174

Inspecting the injector circuit



Check the resistance at the injector ends: 14.5 ± 5% Ohm


load.




INJEC - 175






87 of the solenoid.


INJEC - 176











INJEC - 177







INJEC - 178

With the control unit and the injector disconnected,

check the continuity of the Red-Yellow cable be-

tween pin 14 of the interface wiring and the injector

connector

Switch to «ON» and check if there is voltage, with

injector disconnected and control unit connected,

between the Black-Green cable of the injector con-

nector and the ground lead

With injector disconnected and the injector load

solenoid disconnected, check the continuity of the

Black-Green cable between the injector connector

and solenoid base.

Inspecting the injector hydraulics

To carry out the injector check, remove the intake

manifold by removing the three clamping screws

at the head and the clip connecting the control unit

to the manifold.


INJEC - 179

Install the appropriate tool for checking fuel pres-

sure and position the manifold over a container

graduated by at least 100 cm³. Connect the injec-

tor with the cable making up part of the supply for

the injection tester. Connect the clamps of the ca-

ble to an auxiliary battery. Activate the fuel pump

with the active diagnosis. Check that, within fifteen

seconds, approximately 40 cm³ of fuel is dis-

pensed with an adjustment pressure of approxi-

mately 2.5 BAR.

Specific tooling020480Y Petrol pressure check kit

Proceed with the injector seal test.

Dry the injector outlet with a blast of compressed

air. Activate the fuel pump. Wait for one minute,

making sure there are no leaks coming from the

injector. Slight oozing is normal.

Value limit = 1 drop per minute


INJEC - 180

Components location


INJEC - 181

TRANSPARENCYSpecification Desc./Quantity

1 Throttle body and electronic injection control unit (MIU)2 Fuel injector3 Instrument panel4 Injection load solenoid5 Water temperature sensor6 Fuel pump7 HV coil8 Lambda probe9 Speed sensor10 Battery 12V - 12 Ah11 Diagnostics socket connector

Tachometer

With wiring disconnected from the control unit and

connected to the system, check that the sensor

resistance between pins 13 - 15 is between 100

and 150 Ohm at an engine temperature of approx-

imately 20°

Disconnect the fuel pipe connector. Start up the

engine and wait for it to stop. With the wiring con-

nected to the control unit and system try to start up

the engine and check that the voltage between

pins 13 and 15 is around 2.8 V


INJEC - 182

With the interface cabling disconnected from the

control unit, check for continuity between pin 13

and the red cable of the rev sensor connector and

between pin 15 and the white cable of the rev sen-

sor connector.

With the interface wiring disconnected from the

control unit and rev sensor connector, check that

the red and white cables (pin 13 - 15) are isolated

from each other and insulated from the earth.

Specific tooling020481Y Control unit interface wiring



INJEC - 183

HT coil



The ignition system is integrated with the injection and it is a high-efficiency inductive type ignition.

The control unit manages two important parameters:

- Ignition advance

This is optimised according to the engine rpm, to the engine load, temperature and ambient pressure

With idle engine, it is optimised to obtain the stabilisation of the speed at 1450 ± 50 R/1'.

- Magnetisation time

The coil magnetisation time is controlled by the control unit. The ignition power is increased during the

engine start-up phase.

The injection system recognises the 4-stroke cycle and therefore, ignition is only controlled during

compression.



INJEC - 184


load.








87 of the solenoid.


INJEC - 185











INJEC - 186







INJEC - 187

Check there is voltage between pins 22 and 26 of

the interface wiring for around two seconds when

switching to «ON».

Check the resistance of the primary coil between

pin 22 of the interface wiring and the green black

cable of the injection load solenoid base with the

control unit disconnected and the solenoid discon-

nected.

Resistance of the primary = 0.5 ± 8% Ohm


INJEC - 188

Coolant temperature sensor

TEMPERATURE SENSOR 1Specification Desc./Quantity

1 Water temperature sensor2 engine stop switch

With the control unit side connector disconnected

and the coolant temperature sensor connector

connected, check the resistance between pins 9

and 26 in relation to the engine temperature.

20° = 2500 ± 100 Ω

80° = 308 ± 6 Ω

With the control unit side connector disconnected

and the coolant temperature connector discon-

nected, check the insulation between the two light

blue/green and pink/yellow cables


INJEC - 189

Zeroing the throttle

Resetting the throttle valve position signal (TPS reset)

The MIU control unit is supplied with a throttle valve position sensor that is pre-calibrated.

Pre-calibration entails regulating the minimum opening of the throttle valve to obtain a certain flow of

air under pre-set reference conditions.

Pre-calibration ensures optimal air flow to control idling.

This regulation must not be tampered with in any way whatsoever.

The injection system will complete the management of the idling through the Stepper motor and the

variation of the ignition advance.

The throttle body after the pre-calibration has an opened valve with an angle that can vary depending

on the tolerances of the machining of the pipe and the valve itself.

The valve position sensor can also assume various fitting positions. For these reasons the mV of the

sensor with the valve at idle can vary from one throttle body to another.

To obtain the optimum fuel mixture, especially at small openings of the throttle valve, it is essential to

match the throttle body with the control unit following the procedure known as TPS resetting.

With this operation we inform the control unit, as the starting point, of the mV value corresponding to

the pre-calibrated position.

To reset, proceed as follows.

Connect the diagnostic tester.

Switch to «ON».

Select the functions of the diagnostic tester on

«TPS RESET».

Specific tooling020680Y Diagnosis Tool


INJEC - 190

Make sure that the throttle valve with the control is

supporting the stop screw.

Guaranteeing that this position will be kept, send

a confirmation for the TPS reset procedure.

Reset should be performed in the following cases:

- on first fitting.

- if the injection control unit is replaced.N.B.THE TPS RESET PROCEDURE MUST NOT BE CARRIED OUT WITH A USED THROTTLE BODYBECAUSE POSSIBLE VALVE WEAR AND STOP WEAR FOR THE MINIMUM OPENING MAKE THEAIR FLOW DIFFERENTLY FROM THAT OF PRE-CALIBRATION.


INJEC - 191

Given that the TPS resetting is also done when the

control unit is replaced, place the control unit - filter

box bellows at 45° during the refitting operation as

shown in the picture.

Lambda probeSIGNAL CONTROL

Install the electronic control unit interface wiring.

Start the engine and warm up until the electric fan

switches on.

Use an analogue multimeter with a direct voltage

scale measuring down to 2 V.

Place the tips of the multimeter between pins 4 (-)

and 11 (+)

With the engine running at idle speed, check that

the voltage oscillates between 0V and 1V

With the throttle valve completely open, the volt-

age is approx. 1V.

During the closing phase, the voltage is approx.

0V.

If the voltage remains constant, the sensor may be

damaged. Remove the sensor and check that

there are no oil or carbon deposits inside it..


INJEC - 192



The Lambda probe or oxygen sensor is a sensor which provides indications concerning the oxygen

content in the exhaust gas. The signal generated is not of the proportional type but of the ON/OFF type,

i.e. there is oxygen or there is not. The sensor is positioned on the exhaust manifold before the catalytic

converter in an area where the gas temperature is always high. The temperature at which the sensor

works is at least 350°C at 600°C and it has a reaction time of just 50 milliseconds. The signal generated

passes from a high value to a low value with a mixture with lambda =1. Since the sensor only works at

high temperatures, it has an electric preheating element inside it, controlled by the control unit, to take

it quickly to the functioning state.

Specific tooling020481Y Control unit interface wiring



INJEC - 193


load.








87 of the solenoid.


INJEC - 194











INJEC - 195







INJEC - 196

INDEX OF TOPICS

SUSPENSIONS SUSP

This section is dedicated to operations that can be carried out on the suspensions.

Front

Removing the front wheel

- Remove the fixing nut from the wheel axle on the

left side of the vehicle.

- Loosen the two screws fixing the wheel axle

clamp and remove the clamp.

Front wheel hub overhaul

Check that the wheel bearings do not show signs

of wear.

If you have to replace the wheel bearings, proceed

as follows:

- Remove the two bearings on the brake disc side

using pliers 14 and the special bell 9.

- Remove the internal spacer.

Suspensions MSS Nexus 125 i.e. (2008)

SUSP - 198

- Support the front wheel with two wooden shims

that make it possible to avoid scratching in the

case of contact with the rim.

- Insert the punch (consisting of adaptor handle,

24 mm adaptor and 15 mm guide) from the brake

disc side to permit the removal of the opposite side

bearing and the spacer bushing.


020456Y Ø 24 mm adaptor

020412Y 15-mm guide

- Heat the bearing seat on the side opposite the

brake disc with the heat gun.

- Insert the bearing using the punch consisting of

adaptor handle, 40x37 mm adaptor and 15 mm

guide, and take it to the stop.

MSS Nexus 125 i.e. (2008) Suspensions

SUSP - 199

- Reinsert the spacer bushing on the brake disc

side using the appropriate tool and take it to the

stop.



020412Y 15-mm guide

020201Y Spacer bushing driving tube

- Refit the cap and tighten the five fixing screws.


SUSP - 200

- Turn over the wheel and insert the internal spacer

with the part fitted with the Seeger ring facing the

bearing on the brake disc side.

- Heat the bearing seat on the side the brake disc

with the heat gun.

2 - Insert the two bearings one at a time using the punch consisting of adaptor handle, 32x35 mm

adaptor and 15 mm guide, and take it to the stop.



020412Y 15-mm guide

Refitting the front wheel

- When refitting, pay attention in repositioning the

odometer drive correctly.

Locking torques (N*m)Wheel axle nut 45 to 50 Wheel axle clampscrews 6 - 7 Nm

Handlebar


SUSP - 201

Removal

• Remove the two handlebar covers as

explained in the Bodywork Chapter.

• Remove the handlebar wiring fixing

clips and disconnect the electric con-

nectors from the brake levers.

• Unscrew the fittings, then remove the

front and rear brake pump piping.

• Remove the flexible transmission of

the accelerator and remove the throt-

tle.

• Loosen the clamp fixing the handlebar

to the steering tube and pulling up-

wards, remove the handlebar, then re-

move the lower plastic cover.N.B.IF THE HANDLEBAR IS BEING REMOVED TO REMOVETHE STEERING, IT IS ONLY NECESSARY TO TILT THEHANDLEBAR FORWARD ONTO THE FRONT PART OF THEVEHICLE WITHOUT REMOVING THE PARTS FITTED SOAS TO AVOID DAMAGING THE SHAFTS.

Refitting

Carry out the above operations by working in the reverse order from that used for removal.

Locking torques (N*m)Handlebar fixing screw (*) 43 ÷ 47

Front fork

Removal

See alsoRemoval


SUSP - 202

Overhaul

- Support the fork in a vice.

- Loosen the two tightening screws of the stem

supporting clamp.

- Unscrew the stem closing cap and slide off the

complete fork leg from the corresponding support.CAUTIONTHE STEM CLOSING CAP KEEPS THE MAIN SPRING PRE-LOADED. KEEP THE CAP PROPERLY FITTED DURINGTHE REMOVAL FINAL STAGE TO AVOID ACCIDENTS.

- Support the fork leg properly, remove the main

spring and drain off the fork leg oil.

- Remove the hydraulic rod fixing screw with the

corresponding sealing gasket:

- With a 19-mm hexagonal spanner, lock hydraulic

rod rotation.

- Undo the fixing screw and collect the copper

washer.


SUSP - 203

- Remove the stem dust guard with a screwdriver.

- Remove the circlip retaining the oil seal.

- Take out the stem.

- Check there are no signs of wear or seizing between the stem and the fork leg. Otherwise, replace

the damaged parts.

CharacteristicMaximum fork leg diameter

35.10 mm

Minimum stem diameter

34.90 mm


SUSP - 204

- Take out the oil seal using the appropriate tools.

- Fit the tie rod into the oil seal.

- Insert in sequence the two half-rings per Ø 35-

mm stems.

Specific tooling020487Y Fork oil seal extractor

- Hold the tie rod manually so that it does not fall

into the fork leg and/or that both half-rings are not

in their position.

- Fit the bell.

- Tighten the nut until it stops.

- Act on the tool until the oil seal is completely re-

moved.

Specific tooling020487Y Fork oil seal extractor

- Remove the hydraulic rod with the corresponding

sealing gasket, the spring and the stop bushing.

COMPONENT CHECKCAUTION

CLEAN ALL THE COMPONENTS THOROUGHLY.


SUSP - 205

- Check that the fork leg is not cracked or broken

in the attachments.

- Check that the stem is not scored, dented or dis-

torted.

- Check that the stop bushing for the hydraulic rod

is correctly fixed through caulking.

- Check that hydraulic rod caulkings, the return

spring to the unloaded the end of stroke and the

hydraulic rod sealing ring are in good conditions.

- Check that the main spring exhibits no signs of

yielding or abnormal wear.


SUSP - 206

- Check that the closing cap O-ring of the stem is

in good conditions.

Refitting

- First grease the splitting chamber of the two seal-

ing lips of a new oil seal.

- Fit the sealing ring on the stem and keep the

identification words facing upwards.

- Drive the oil seal as far as it will go using the ap-

propriate tool.



- Pre-fit the stem with the hydraulic rod, the spring

and the stop bushing.

- Fit the pre-assembled components inside the fork

leg.

- Fit the hydraulic rod fixing screw with the copper

sealing washer and tighten to the prescribed tor-

que using the recommended product.CAUTIONALWAYS USE NEW COPPER WASHER.

Locking torques (N*m)Hydraulic rod fixing screw 25 ÷ 35*

(°) Apply LOCTITE 243 threadlock


SUSP - 207

- Lock hydraulic rod rotation using a 19-mm hex-

agonal spanner.

- Fit the oil seal retaining circlip.

- Grease and fit a new dust guard.

- Fit the fork leg together with the stem on the fork

supporting clamp until it stops.

- Tighten the two screws to the prescribed torque

in the sequence indicated in the picture.

Locking torques (N*m)Stem support clamp tightening screws 20 to 25


SUSP - 208

- Refill the fork leg with the recommended product

to the prescribed amount.

Recommended productsAGIP FORK 7.5 W Oil for front forkHydraulic fluid SAE 7.5 W

CharacteristicOil quantity per stem133 ± 3 cm³

- Bleed the hydraulic rod by actuating the stem re-

peatedly.

- Fit the spring into the stem.CAUTION

FIT THE SPRING WITH THE SMALLER PITCH TO THE UP-PER PART OF THE STEM.

- Lubricate the closing cap O-ring of the stem.

- Preload the spring, fit the closing cap and tighten


Locking torques (N*m)Fork locking screws cap 15 ÷ 30

- Repeat the procedure for the other fork leg.N.B.

IF BOTH FORK LEGS ARE SERVICED AT THE SAME TIME, BE CAREFUL NOT TO INVERT THERIGHT FORK LEG WITH THE LEFT ONE.


SUSP - 209

Steering column

Removal

- Remove the front wheel.

- Remove the front mudguard

- Remove the front brake calliper

- Remove the shield back plate upper side.

- Remove the pin mounting the handlebar to the

steering tube.

- Remove the handlebar and rest it on the shield

back plate.

- Remove by releasing the cable passages and

sliding the protection collar upwards.

- Using the appropriate tool, loosen and remove

the upper ring nut, the space washer, the counter

ring nut and the spacer.

- Remove the cover plate and upper seat of the

steering fifth wheel.

- Extract the fork.N.B.TAKE CARE TO SUPPORT THE FORK SO AS TO PREVENTIT FROM COMING OFF ABRUPTLY

Specific tooling020055Y Wrench for steering tube ring nut


SUSP - 210

Refitting

- Fit the lower steering bearing on the steering

tube.

- Fit the fork together with the lower steering bear-

ing on the headstock and hold it so that it does not

fall.N.B.LUBRICATE THE STEERING FIFTH WHEEL TRACKS WITHRECOMMENDED GREASE BEFORE USE.

Recommended productsAGIP GREASE PV2 Grease for steering bear-ings, bolt seatings for swinging arms and fay-ing surface of driven pulley spring (only pulleyside)Soap-based lithium and zinc oxide grease con-

taining NLGI 2; ISO-L-XBCIB2

- Fit the upper steering bearing.CAUTIONINSERT THE UPPER STEERING BEARING WITH THECAGE FACING UPWARDS.

- Fit the steering bearing upper seat.


SUSP - 211

- Fit the cover plate.

- Insert the spacer.

- Insert the lower tightening ring nut, screw until it

stops and, with the specific tool, tighten to the pre-

scribed torque.


Locking torques (N*m)Steering tube lower ring nut 14 ÷ 17


SUSP - 212

- Fit the spacer between the two ring nuts on the

steering tube in the position indicated.

- Insert the upper tightening ring nut, screw until it

stops and, with the specific tool, tighten to the in-

dicated torque.


Locking torques (N*m)Steering tube upper ring nut 40 ÷ 45

Insert the collar shown in the figure and restore the

cable passage as shown in the figure.

- Fit the front wheel.

Steering bearing


SUSP - 213

Removal

- Clean thoroughly and visually inspect if the com-

ponents are in good conditions.

- Check the upper steering bearing for wear.

- Check the lower steering bearing for wear.

- Visually inspect that the steering fifth wheel

tracks, the headstock and the steering tube exhibit

no scores or abnormal wear. Otherwise, replace

them.

STEERING FIFTH WHEEL TRACK REMOVAL

- Remove the steering fifth wheel tracks on the

chassis with the specific tool, following the indica-

ted procedure.

- Fit the specific tool from the lower part of the

headstock until it makes contact with the upper

track.

- Hit with force the specific tool, placing it at differ-

ent points diametrically opposed so as to remove

the upper track.

Specific tooling020004Y Punch for removing steering bearingsfrom headstock


SUSP - 214

- Repeat the procedure for the lower steering bearing track.

- Remove the lower steering bearing seat on the

steering tube using the specific tool.

Specific tooling020004Y Punch for removing steering bearingsfrom headstock


SUSP - 215

Refitting

STEERING FIFTH WHEEL TRACK FITTING

- Thoroughly clean the track seats on the head-

stock and the steering tube.

- Fit the new tracks of the headstock with the spe-

cific tool.

- Screw the nut until the tracks are fully inserted.N.B.LUBRICATE THE STEERING FIFTH WHEEL TRACKS WITHRECOMMENDED GREASE BEFORE USE.

Specific tooling001330Y Tool for fitting steering seats

Recommended productsAGIP GREASE PV2 Grease for steering bear-ings, bolt seatings for swinging arms and fay-ing surface of driven pulley spring (only pulleyside)Soap-based lithium and zinc oxide grease con-


- Fit the lower fifth wheel seat on the steering tube.

- Using the specific tool, fit the lower fifth wheel

seat on the steering tube.N.B.LUBRICATE THE STEERING FIFTH WHEEL TRACKS WITHRECOMMENDED GREASE BEFORE USE.

Specific tooling020459Y Punch for fitting bearing on steeringtube

Recommended productsAGIP GREASE PV2 Grease for steering bear-ings, bolt seatings for swinging arms and fay-


SUSP - 216

ing surface of driven pulley spring (only pulleyside)Soap-based lithium and zinc oxide grease con-


Rear

Removing the rear wheel

- Remove the mudflap undoing the four screws.

- Remove the exhaust silencer.

- Remove the cotter pin.

- Remove the cap.


SUSP - 217

- Unscrew the wheel fixing nut and collect the

spacer.

- Unscrew the shock absorber fixing nut on the

right of the bracket.

- Undo the two screws fixing the bracket to the en-

gine and remove the bracket.

- Collect the spacer.

- Undo the five wheel fixing screws and collect the

wheel.

Refitting the rear wheel

To fit, follow the removal procedure but in reverse order.

Locking torques (N*m)


SUSP - 218

Silencer arm clamping screws 27 - 30 Rear wheel axle nut 104 to 126 Shock absorber-crankcaseattachment bracket 20 to 25 Lower shock absorber clamping screw 33 - 41 Nm Rear brake cal-liper fixing screws 25 - 30 Nm

Swing-arm

Removal

- Place the vehicle on its centre stand;

- Remove the swinging arm/engine fitting shown in

the picture

- Move the engine back

- Remove the spring anchoring the swinging arm

to the chassis as shown in the picture

- Remove the buffer cover undoing the screws in-

dicated .


SUSP - 219

- Remove the clamp by undoing the screw indica-

ted..

- Unscrew the two«A» screw on each side of the

vehicle.

- Unscrew the «B» nut and extract the pin from the

opposite side.

- Check the entire swinging arm assembly.

- Check all the centring bushing components and silent block rubber buffers.

- Replace the work components that cause excessive clearance on the rear suspension.

Overhaul

- Make sure the silent bloc is not broken. If it is,

replace the coupling.

- Remove the Seeger ring shown in the picture


SUSP - 220

- Remove the full silent bloc bracket

- Undo the silent bloc ring shown in the picture

- Hold the full silent bloc bracket in the clamp

- Using the appropriate tool, remove the silent bloc

from the bracket from the side corresponding to

the inside of the vehicle. This is to guarantee the

tool is centred properly on the support

- Install a new silent bloc, making sure it aligns

properly with the reference tooth.

- Fit the silent blocs, making sure the chamfered

part of the silent bloc matches the chamfered part

of the bracket


SUSP - 221

- Using the appropriate tool, fit the silent bloc as

shown in the picture

- Check there is no sticking in the movement of the

connection of the swinging arm on the engine side

to the swinging arm on the chassis side.

- Check the axial clearance between the two

swinging arms using a feeler gauge

CharacteristicStandard clearance0.40 - 0.60 mm


- To check the clearance on the chassis-side arm,

mount the retainer using the pin fixing the swinging

arm to the chassis and two adaptor rings of the

appropriate tool 020229Y. Alternatively use two

washers with inner diameter for 12-mm pins, min.

outer diameter: 30 mm: min. thickness: 4 mm.

- Check there is no sticking in the rotation.

- Check the axial clearance of the swinging arm on

the chassis side

CharacteristicStandard clearance0.40 - 0.60 mm



SUSP - 222

- Separate the swinging arm on the engine side

from the vehicle side arm.

- Remove the plastic bushings and the internal

spacer shown in the picture.

- Using a suitable pin remove the roller casings as

shown in the pictures

- Using an appropriate tool plant new roller cas-

ings, being careful to position the bearings with the

seal rings facing outwards

Specific tooling020244Y 15-mm diameter punch

020115Y Ø 18 punch

CharacteristicLength of the swinging arm tube on the engineside:L 175.3 + 0.3 0

Length of the internal swinging arm spacer onthe engine side:L 183 + 0.3 0

Engine side swinging arm plastic bushingshim:3.5 ± 0.05 mm

Chassis side swinging arm plastic bushingshim:3.5 ± 0.05 mm

Length of the internal swinging arm spacer onthe chassis side:290 ± 0.1 mm


SUSP - 223

Length of the swinging arm tube on the chas-sis side:283 ± 0.1 mm

- Lubricate roller casings and the plastic bushings with grease

- Insert the spacers

- Assemble the two arms with the relative bolt in the position shown in the picture

- Adjust the bolt as shown in the picture

- Position the chassis side swinging arm with the most protruding part pointing towards the silent block

side as shown in the picture

Recommended productsAGIP GREASE PV2 Grease for steering bearings, pin seats and swinging arm

Soap-based lithium and zinc oxide grease containing NLGI 2; ISO-L-XBCIB2 of the swinging arm

Refitting

- To refit, perform the removal operations in reverse.

- Grease the bearings and the rolling parts with the recommended grease.

-Complete the fitting by tightening the nuts on the relative bolts to the proper tightening torque.

See alsoTightening Torques

Shock absorbers

Removal

Proceed as follows:

- place the vehicle on its centre stand;

- lift the engine a little with a jack so as to free the

two shock absorbers;

- remove the silencer

- undo the shock absorber spring assembly clamp-

ing screw from the support fixed to the engine on

the one side and from that fixed to the silencer on

the other;

- unscrew the two upper nuts (one on each side)

fixing the shock absorber spring assembly to the

frame and remove the shock absorbers.


SUSP - 224

Refitting

Carry out the previous operations but in reverse order.

Locking torques (N*m)Shock absorber lower clamping 33 to 41 Shock absorber upper clamp 33 to 41

Centre-stand

REMOVAL

- Use a jack to support the vehicle properly.

- Remove the two return springs from the centre

stand.

- Undo the nut shown in the figure.

- Remove the pin from the right side.

- Remove the centre stand.

FITTING

- On refitting tighten the nut to the specified torque.

Locking torques (N*m)Centre stand bolt 32 to 40

Side stand

REMOVAL

- Uncouple the centre stand return spring;

Remove the screw shown in the photograph

FITTING

To refit, carry out the removal operations in re-

verse order and comply with the specified torque.

Locking torques (N*m)Side stand fixing bolt 35 to 40


SUSP - 225


SUSP - 226

INDEX OF TOPICS

BRAKING SYSTEM BRAK SYS

This section è is dedicated to the description of the brake system components.

Rear brake calliper

Removal

- Remove the rear wheel.

- Remove the two rear brake calliper devices fas-

tening them to the support as shown in the picture.N.B.IF IT IS NECESSARY TO REPLACE OR SERVICE THEBRAKE CALLIPER, BEFORE REMOVING THE FITTINGSFIXING THE CALLIPER TO THE SUPPORT BRACKET,FIRST LOOSEN THE OIL HOSE FITTING AFTER HAVINGEMPTIED THE SYSTEM OF THE CIRCUIT BEING EXAM-INED.

Overhaul

- Remove the brake calliper.

- Suitably support the brake calliper in a vice

- Remove the two pad fixing screws.

- Remove the pads being careful with the stop

spring.

- Remove the fixed plate by undoing the screw

shown in the photograph.

Braking system MSS Nexus 125 i.e. (2008)

BRAK SYS - 228

- Remove the internal parts from the floating body

with short blasts of compressed air through the

brake liquid pipe to facilitate expelling the plung-

ers.

- Check:

• that the plates and the body are whole

and in good condition;

• that the cylinders of the calliper floating

body do not show signs of scratches or

erosion, otherwise replace the entire

calliper:

• that the guides of the fixed plate are not

scratched or eroded, otherwise re-

place the entire plate;

• that the brake pad check spring works

properlyCAUTIONALL THE SEALS AND GASKETS MUST BE REPLACED EV-ERY TIME THE PUMP IS SERVICED.

Refitting- Insert the O-rings and small pistons the floating

body, lubricating all the components with brake

fluid.

- Fit the fixed plate being careful to grease the

guide «A» and to insert washer «B» correctly as

indicated in the photo.

- Fit the pad retention spring

- Fit the pads and screw up the relative clamping screws to the specified torque

MSS Nexus 125 i.e. (2008) Braking system

BRAK SYS - 229

- Hold the pads in the correct position and insert the calliper in the brake disc.

- Fix the support calliper by means of the two screws at the specified torque

- Secure the pipe fitting to the calliper at the specified torque.

- Bleed the air from the system.

Front brake calliper

Removal

- Remove the two front brake calliper devices fas-

tening them to the support as shown in the photo-

graph.N.B.WHEN A PROCEDURE IS PLANNED INCLUDING THESERVICE OR REPLACEMENT OF THE CALLIPER, FIRSTLOOSEN THE FITTING CONNECTING THE PIPE TO THEBRAKE CALLIPER

Overhaul


- Suitably support the brake calliper in a vice

- Remove the two pad fixing screws.

- Remove the pads being careful with the stop

spring.

- Remove the fixed plate by undoing the screw

shown in the photograph.


BRAK SYS - 230

- Remove the internal parts from the floating body

with short blasts of compressed air through the

brake liquid pipe to facilitate expelling the plung-

ers.

- Check:

• that the plates and the body are whole

and in good condition;

• that the cylinders of the calliper floating

body do not show signs of scratches or

erosion, otherwise replace the entire

calliper:

• that the guides of the fixed plate are not

scratched or eroded, otherwise re-

place the entire plate;

• that the brake pad check spring works

properlyCAUTIONALL THE SEALS AND GASKETS MUST BE REPLACED EV-ERY TIME THE PUMP IS SERVICED.

Refitting- Insert the O-rings and small pistons the floating

body, lubricating all the components with brake

fluid.

- Fit the fixed plate being careful to grease the

guide «A» and to insert washer «B» correctly as

indicated in the photo.

- Fit the pad retention spring

- Fit the pads and screw up the relative clamping screws to the specified torque


BRAK SYS - 231

- Hold the pads in the correct position and insert the calliper in the brake disc.

- Fix the support calliper by means of the two screws at the specified torque

- Secure the pipe fitting to the calliper at the specified torque.

- Bleed the air from the system.

Rear brake disc

Removal

- Remove the rear wheel.


- Remove the disc from the wheel axle.

- Undo the five screws and remove the disc from

the wheel hub.

Refitting

Follow the removal operations but in reverse order.N.B.THE ARROW STAMPED ON THE DISC INDICATING THE RUNNING DIRECTION MUST BE FITTEDTOWARDS THE OUTSIDE OF THE VEHICLE.

Recommended productsLoctite 243 Medium strength threadlockMedium Loctite 243 threadlock

Locking torques (N*m)Brake disc fixing screw 5 to 6.5

Disc Inspection

- Remove the rear brake calliper.


BRAK SYS - 232

- Check the disc thickness with a micrometer

CharacteristicStandard thickness:

5 +0.2-0.1 mm

- Repeat the measurement at no fewer than six points on the disc.

- Check the regular nature of the rotation of the brake disc assembly using the appropriate tool fixed

onto the brake calliper as shown in the photo.

- In order to be able to anchor the appropriate tool properly use a metal plate with M8 threaded hole

and fix it to one of the two rear brake calliper attachment points.

- Suitably fix the flange to the wheel axle with the original nut and spacer and a Æ 17 mm bearing.N.B.

SO AS NOT TO GET A DISTORTED READING, CAUSE THE DRIVEN PULLEY SHAFT TO TURNIN ORDER TO ROTATE THE DISC.

Specific tooling020335Y Magnetic mounting for dial gauge

CharacteristicMax. deviation allowed:

0.1 mm

- If you detect incorrect values, replace the disc. If

the anomaly persists, replace the hub.

Front brake disc


BRAK SYS - 233

Removal

- Remove the front wheel.

- Undo the five clamping screws shown in the pho-

tograph

Refitting

For fitting, position the disc correctly using the arrow stamped on it as reference.

- Do up the screws to the prescribed torque and apply the recommended productN.B.

THE ARROW STAMPED ON THE DISC INDICATING THE RUNNING DIRECTION MUST BE FITTEDTOWARDS THE OUTSIDE OF THE VEHICLE.



Locking torques (N*m)Brake disc fixing screw 5 to 6.5

Disc Inspection

Checking the disc is important; it must be perfectly clean, with no sign of rust, oil or grease or any other

dirt, and must show no signs of deep scoring.

CharacteristicNew rear disc thickness

4.0 mm

Disc thickness at wear limit (front)

3.5 mm


BRAK SYS - 234

• Using the appropriate tool, measure

how much the disc protrudes when the

wheel is fitted properly. The protrusion,

measured near the external edge of

the disc, must be less than 0.1 mm.

• If a value is measured other than the

specified value, remove the front wheel

(Front/Rear Suspension chapter) and

check the protrusion of the disc. Maxi-

mum permissible out of true is 0.1 mm.

If the value measured is greater, re-

place the disc and repeat the check.

• If the problem persists, check and re-

place the wheel hub if necessary.

Specific tooling020335Y Magnetic mounting for dial gauge

Front brake pads

Removal

Proceed as follows:

- Remove the front brake calliper.

- Loosen the two pins shown in the figure that lock

the two pads.

- Remove the pads, being careful with the pad

spring clamp.

- Check the thickness of the pads.

CharacteristicMinimum value1.5 mm


BRAK SYS - 235

See alsoFrontbrake calliper

Refitting

To fit, proceed as follows:

- Insert the two pads in the callipers.

- Screw the two pad lock pins to the correct torque, and apply the recommended product.

- Fit the calliper on its support, tightening the two screws to the prescribed torque.N.B.

IF IT IS NOT POSSIBLE TO CORRECTLY POSITION THE CALLIPER ON THE DISC DURING FIT-TING, GENTLY EXPAND THE PADS.



Locking torques (N*m)Screw tightening calliper to support 24 to 27 Pad fastening pin 19.6 ÷ 24.5

Rear brake pads


BRAK SYS - 236

Removal

Proceed as follows:

- Remove the rear brake calliper.

- Loosen the two pins shown in the figure that lock

the two pads.

- Remove the pads, being careful with the pad

spring clamp.

- Check the thickness of the pads.

CharacteristicMinimum value1.5 mm

See alsoRemoval


BRAK SYS - 237

Refitting

To fit, proceed as follows:

- Insert the two pads in the callipers.

- Screw the two pad lock pins to the correct torque, and apply the recommended product.

- Fit the calliper on its support, tightening the two screws to the prescribed torque.N.B.

IF IT IS NOT POSSIBLE TO CORRECTLY POSITION THE CALLIPER ON THE DISC DURING FIT-TING, GENTLY EXPAND THE PADS.



Locking torques (N*m)Screw tightening calliper to support 24 to 27 Pad fastening pin 19.6 ÷ 24.5

Fill

Rear - combined

- Remove the rubber cap from the bleed screw.

- Insert a rubber pipe in the bleed screw to permit

the brake fluid to be recovered.

- With the left-had brake lever, load the system and

bring it up to the required pressure.

- Keeping the left-hand brake lever pulled, loosen

the bleed screw to permit the air in the system to

escape. Then tighten the bleed screw

- Repeat the operation until only brake fluid comes out of the rubber pipe.

- Remove the fluid recovery pipe and refit the rubber cap over the bleed screw.

- Top up the brake fluid to the right level in the reservoir.

If necessary, bleeding can be done using a special vacuum pumpN.B.

DURING THE BLEEDING OPERATIONS, MAKE SURE THE BRAKE FLUID DOES NOT COME INTOCONTACT WITH THE BODYWORK SO AS NOT TO DAMAGE IT. FURTHERMORE, DURING THEBLEEDING OPERATIONS REGARDING THE BRAKE CALLIPERS, MAKE SURE THE BRAKEFLUID DOES NOT COME INTO CONTACT WITH THE DISC BRAKES AND WITH THE BRAKEPADS. FAILURE TO OBSERVE THIS PRECAUTION WILL ENDANGER THE PROPER WORKINGAND EFFICIENCY OF THE BRAKING SYSTEM

Specific tooling020329Y Mity-Vac vacuum-operated pump



BRAK SYS - 238

System bleed calliper fitting: 12 ÷ 16 Nm

Front

- Remove the rubber cap from the bleed screw.

- Insert a rubber pipe in the bleed screw to permit

the brake fluid to be recovered.

- With the right-hand brake lever, load the system

and bring it up to the required pressure.

- Keeping the right-hand brake lever pulled, loosen

the bleed screw to purge the air. Then tighten the

bleed screw

- Repeat the operation until only brake fluid comes out of the rubber pipe.

- Remove the fluid recovery pipe and refit the rubber cap over the bleed screw.

- Top up the brake fluid to the right level in the reservoir.

If necessary, bleeding can be done using a special vacuum pumpN.B.

DURING THE BLEEDING OPERATIONS, MAKE SURE THE BRAKE FLUID DOES NOT COME INTOCONTACT WITH THE BODYWORK SO AS NOT TO DAMAGE IT. FURTHERMORE, DURING THEBLEEDING OPERATIONS REGARDING THE BRAKE CALLIPERS, MAKE SURE THE BRAKEFLUID DOES NOT COME INTO CONTACT WITH THE DISC BRAKES AND WITH THE BRAKEPADS. FAILURE TO OBSERVE THIS PRECAUTION WILL ENDANGER THE PROPER WORKINGAND EFFICIENCY OF THE BRAKING SYSTEM

Specific tooling020329Y Mity-Vac vacuum-operated pump

Locking torques (N*m)System bleed calliper fitting: 12 ÷ 16 Nm

Front brake pump

Removal

The procedure is valid for both brake pumps.

- Remove the front and rear handlebar covers.

- Place a suitable container to collect the oil, dis-

connect the oil pipe from the calliper and operate

the brake lever until no more oil comes out.

- Disconnect the oil pipe «A» from the pump, then

unscrew the two retainers «B» from the U-bolt and

remove the pump.


BRAK SYS - 239

- Upon refitting, tighten up the fitting to the speci-

fied torque and bleed the system.

Locking torques (N*m)Brake fluid pump-hose fitting 16 - 20


BRAK SYS - 240

INDEX OF TOPICS

COOLING SYSTEM COOL SYS

Circuit diagram

Key

A = entering the engine (cold)

B = electric pump

C = thermostat with by-pass

D = leaving the engine (hot)

E = radiator

F = expansion tank

This is a forced circulation cooling system, with continuous purging and air pressurisation. Circulation

takes place by means of an electric centrifugal pump which sends coolant to the thermal group. The

thermostat is connected at the head output. The radiator output is directly connected to the pump. The

expansion tank is connected to the radiator: the radiator hot-box is connected to the upper side of the

expansion tank (in air); the radiator cold-box is connected to the lower side of the expansion tank (in

fluid).

CharacteristicCooling system capacity:

~ 2 l

TECHNICAL SPECIFICATIONSSpecification Desc./Quantity

Cooling system capacity: ~ 2 l

Cooling system MSS Nexus 125 i.e. (2008)

COOL SYS - 242

Specification Desc./QuantityRecommended fluid AGIP PERMANENT SPEZIAL (ready for use)

Sealing pressure Cap calibrated at 0.9 bar

THERMOSTATSpecification Desc./Quantity

Type Wax-type, with deviatorStarts opening at 85 ± 2°C

ELECTRIC VENTILATIONSpecification Desc./Quantity

Electric ventilation starts at 100° CElectric ventilation stops at 90° C

WATER PUMPSpecification Desc./Quantity

Type CentrifugalControl Electric, commanded by the control unit

RADIATORSpecification Desc./Quantity

Type Aluminium, with horizontal circulation

EXPANSION TANKSpecification Desc./Quantity

Calibration Automatic bleeding, in parallel with the radiator

System bleed

- Start up the engine until the operating tempera-

ture is reached.

- Remove the rubber hood over the bleed valve

- Obtain a rubber tube that is of the right length to

connect the valve to the expansion tank

- Place one end of the pipe on the bleed valve and

the other in the expansion tank

- Loosen the screw by two turns until the commu-

nication hole is revealed with the head as shown

in the picture

- Wait until only coolant comes out of the rubber

pipe so as to eliminate any air bubbles inside the

circuit.

- Tighten the bleed valve respecting the maximum

torque.

- Bring the coolant up to the correct level inside the

expansion tank


MSS Nexus 125 i.e. (2008) Cooling system

COOL SYS - 243

Bleed screw 3

Water pump

KEY

1. Battery

2. Fuse No. 2

3. Ignition key contacts

4. Fuse No. 10

5. Fuse No. 5

6. Injection load solenoid

7. Water pump

8. Injection ECUWARNINGALL CONTINUITY TESTS MUST BE CARRIED OUT WITH THE CORRESPONDING CONNECTORSDISCONNECTED.WATER PUMP CIRCUIT CHECK

1) Check that fuses No. 2, 5 and 11 operate properly.

2) Check the contacts of the key switch and the injection load remote control as described in the "Elec-

trical system" chapter.

3) Check whether there is voltage:

- between the Red-Blue cable of the base of the injection load remote control and the ground lead.

- between the White-Black cable of the base of the injection load remote control and the ground lead,

with the key switch set to «ON».

Cooling system MSS Nexus 125 i.e. (2008)

COOL SYS - 244

4) Check that the cable harnesses are in good condition whenever no voltage is detected.

5) Check whether there is voltage in:

- the Black-Purple cable between the base of the injection load remote control and the control unit (pin

20).

- the Black-Green cable between the base of the injection load remote control and the water pump

connector.

6) Check the pump ground connection (Black cable).

MSS Nexus 125 i.e. (2008) Cooling system

COOL SYS - 245

INDEX OF TOPICS

CHASSIS CHAS

This section è is dedicated to the operations that can be carried out on the vehicle's bodywork.

Seat

Lift the saddle to remove it:

- Push and turn the ignition lock key anticlockwise

until it clicks.

- Lift the saddle.

- Remove the control button of the under seat light.

- Remove the two fixing screws to the chassis.

Rear handlebar cover

- Release the three retaining tabs of the rear han-

dlebar cover shown in the figure using a screw-

driver and paying attention not to damage the

paintwork.

- Remove the five fixing screws from the rear han-

dlebar cover.

- Remove the rear cover.N.B.WHEN INSTALLING, THE CENTRE SCREW IS A METALSCREW, THE OTHER 4 ARE PLASTIC.

MSS Nexus 125 i.e. (2008) Chassis

CHAS - 247

Instrument panel

- Remove the instrument panel.

- Loosen the five fixing nuts of the instrument pan-

el.

Front handlebar cover

- Remove the rear handlebar cover.

- Remove the left and right frames of the brake

pump secured with two retaining fins.

- Loosen the four fixing screws of the front han-

dlebar cover with the handlebar itself.

- Disconnect the warning light unit connector «A».

Chassis MSS Nexus 125 i.e. (2008)

CHAS - 248

Headlight assy.

The front headlight assembly has two units, the

procedure for both is the following:

- Remove the front lower frame (see FRONT

SHIELD).

- To remove the right headlight assembly undo the

two screws «A».

- To remove the left headlight assembly undo the

two screws «B».

- To remove the right assembly, remove the screw

located in the coolant loading compartment.

- To remove the left-hand light assembly, remove

the screw located in the left-hand storage com-

partment.

Remove the light, disconnecting the electric con-

nector from the light and the complete lamp holder

of the position light.N.B.THE TWO REAR ADJUSTMENT SCREWS SHOWN IN THEFIGURE ARE ADJUSTED DURING ASSEMBLY OF THELIGHT AND MUST NOT BE ALTERED.

Frame central cover

The chassis central cover has a central tunnel and two side fairings, the procedure is the following:

CENTRAL TUNNEL:


CHAS - 249

- Remove the saddle together with the hinge.

- Open the fuel tank flap.

- Unscrew the six ring gear fixing screws.

- Remove the clamp indicated.

- Undo and remove from both vehicle sides the

screw indicated in the figure.

- Working from both sides, undo the screw indica-

ted and release the retaining tongues to remove

the side air deflectors.


CHAS - 250

- Undo from both sides the screw indicated in the

figure.

- Remove the central tunnel sliding it from the

tongues.

SIDE FAIRING:


- Remove the side fairings.

- Remove the handgrips and top side fairings.

- Remove the right and left footrests (see FOOTREST).

- Working from both sides, undo the screw indica-

ted in the figure.

- Remove the side fairing sliding it from the

tongues.

Legshield

The front shield has a lot of sections. The removal procedure is described below:

FRONT LOWER FRAME:

- Using a screwdriver, remove the «GILERA» clip-

on badge.


CHAS - 251

- Undo and remove the screw under the badge.

- Undo and remove the screw «A».

- Taking care not to damage the plastic tongues,

remove the front lower frame sliding it upwards

from bottom to top.

FRONT UPPER FRAME:

- Remove the FRONT LOWER FRAME.

- Remove the windshield together with the supports.

- Undo and remove the two screws «B» and the

four screws «C».

- Remove the frame sliding it from the tongues.


CHAS - 252

FRONT TURN INDICATORS:

- Undo and remove the three screws indicated.

- Disconnect the front turn indicator connector.

- Undo and remove the three screws to remove the

bulb holder from the support.

FRONT SHIELD:

- Remove the front lower frame.

- Remove the front upper frame.

- Remove the front headlight assemblies.

- Remove the instrument panel (see SHIELD BACK PLATE).

- Remove the lower shield back plate (see SHIELD BACK PLATE).

- Remove the hand guards unscrewing, from both

sides, the two screws «A» collecting the washers

and the screw «B».


CHAS - 253

- Undo the central screw.


- Undo the rider footrest fixing screw «C» and the

spoiler fixing screw «D».

- Remove the front shield releasing the different

cable harness from the clamps.

To refit follow the reverse order paying attention to fasten the cable harness with the relative clamps.

Knee-guard

The shield back plate is made by two sections. The instrument panel, with instrument unit and lower

shield back plate. The procedure for both is described below:

INSTRUMENT PANEL:

- Remove the windshield.

- Remove the rear handlebar cover.

- Remove the front handlebar cover.

- Remove the handlebar.


CHAS - 254

- Undo and remove the two screws «A».

- Working from both vehicle sides, undo and re-

move the screw «B».

- Undo and remove the two screws «C» placed on

and inside the glove compartment.

- Undo and remove the two screws «D» placed on

and inside the coolant loading compartment.


CHAS - 255

- Undo and remove the expansion tank cap and

the gasket below.

- Remove the instrument panel and release the in-

strument panel connector «E» and the instrument

panel lighting connector «F». Remove the instru-

ment panel.

LOWER SHIELD BACK PLATE:

- Remove the central tunnel (see CENTRAL CHASSIS COVER).

- Remove the instrument panel (see SHIELD BACK PLATE).


move the two screws «A».

- Turn the key switch frame anticlockwise (it may

be necessary to use pliers), releasing the catch.


CHAS - 256

Removing the ignition key-switch when on *off*

- Remove the lower shield back plate.

- Unscrew the seat opening transmission from the

side.

- Remove in advance the ring of the immobiliser

antenna.

- Undo the two hexagonal male screws and re-

move the complete switch.

- From the bottom, it is possible to remove the

three fixing screws and to release the two hook

teeth to raise the retaining plate of the steering lock

strut.

- The latter has a retaining tab with cylindrical teeth

that cannot be replaced.

Front wheel housing

To remove the front wheel housing, proceed as

follows:

- Remove the spoiler.

- Remove the front fork.

- Remove the plate supporting bracket for the horn

and voltage regulator by loosening the two fixing

screws shown in the figure in order to release the

two lower retainers of the wheel housing.

- Remove the upper fixing screw of the wheel

housing to permit movement.


CHAS - 257

- In order to remove the wheel housing it is necessary to remove the front brake hose to the tank and

combination with the splitter.

Taillight assy.

To remove the rear light assembly, proceed as fol-

lows:

- Remove the rear upper central cover.

- Remove the handgrips and the upper side fair-

ings.

- Undo and remove the central screw.

- Using a jointed wrench between the helmet com-

partment and the chassis pipes, loosen the two

rear fixing nuts and then disconnect the light stud

bolts from the support extensions.

- Remove the light and disconnect the bulb holder

by turning it through 30° in anticlockwise direction.

Footrest

The footrest comprises a right and left footrest, a passenger footrest and a rider footrest. The whole

procedure is described below:

PASSENGER FOOTREST:


- Unscrew the nut «A» from both vehicle sides and

release the footrests.


CHAS - 258

RIGHT AND LEFT FOOTREST:

- Working from both vehicle sides, remove the mat.

- Undo and remove the two screws «B» and the

four screws «C».

- Remove the footrest

RIDER FOOTREST:

To remove the rider footrest, proceed as follows:

- Remove the central cover.

- Remove the shield back plate.

- Remove the right and left footrest (see FOOTREST).

- Undo the screw «D» and the screw «E» and re-

move the rider footrest.


CHAS - 259

Side fairings

- Remove the rear central cover.

- Remove the passenger handles.

- Remove the lower cover.

- Remove the lower side cover.

- Remove the eight screws shown in the figure

(four on each side).

- Pull out the fairing.


CHAS - 260

- Remove the three screws indicated in the figure.

License plate holder

- Remove the rear lower central cover.

- Remove the four fixing screws (two per side) and

disconnect the electric connectors.

- To access the license plate light bulb, remove the

two fixing screws of the support rear cover and ex-

tract the complete bulb holder.

Air filter

To remove the complete air filter from the engine,

proceed as follows:

- Undo the two screws «A» and the screw «B»

collecting the washers.


CHAS - 261

- Release the oil recovery pipe releasing the

clamp.

- Undo the three screws and remove the cover of

the air conduit.

- Undo and remove the screw «E».

- Remove the clamp.

- Remove the mudflap.

Rear mudguard

To remove the rear mudguard, proceed as follows:

- From the right side of the vehicle, undo the screw

«A».


CHAS - 262

- From the left side of the vehicle, undo the two

screws «B».

- Remove the rear mudguard.

Helmet bay

To remove the helmet compartment, proceed as follows:

- Remove the saddle.

- Remove the battery.

- Remove the rear upper central cover.

- Remove the handgrips and top side fairings.

- Working from both vehicle sides, undo the three

screws «A» and the screw «B».

- Undo and remove the two screws «C» from the

battery compartment.

- Lift the helmet compartment from the rear side

and remove the saddle lock.

- Disconnect the connectors of the power socket and the under seat light.

- Remove the plug socket due to the interference with the chassis.

- Remove the fuse box releasing the side hook teeth.

- Remove the complete helmet compartment.


CHAS - 263

spoiler

To remove the spoiler, proceed as follows:

- Remove the footrest.

- Working from both vehicle sides, undo the two

fixing screws «A» with the front wheel housing.

- Working from both vehicle sides, undo the fixing

screw «B» with the front shield.


screw «C» with the chassis.


screw «D» with footrest chassis support.

- Slide off the spoiler from the bottom trying not to

touch the side stand.


CHAS - 264

Fuel tank

To remove the fuel tank, proceed as follows:N.B.

THIS OPERATION SHOULD PREFERABLY BE PERFORMED WITH THE TANK EMPTY.


- Remove the central frame cover.

- Remove the footrest.


- Remove the horn plate support bracket and the

voltage regulator unscrewing the two nuts shown

in the figure.

- Disconnect the fuel probe connector.

- Undo the two tank fixing screws.

- Remove the tank through the front lower part of

the vehicle.


CHAS - 265

Rear central cover

- Raise the saddle.

- Remove the two fixing screws shown in the fig-

ure.

- Remove the two screws indicated in the figure.

- Remove the seven screws indicated in the figure.

- Remove the central cover from its retainers.

Front mudguard



Slide the mudguard to the front part of the vehicle.CAUTIONWHEN REFITTING PAY ATTENTION TO THE CORRECTPOSITION OF THE PIPE RETAINING STRAPS.


CHAS - 266

Radiator fan


- Remove the front fork.

- Remove the plate supporting bracket for the horn

and voltage regulator by loosening the two fixing

screws shown in the figure in order to release the

two lower retainers of the wheel housing.

- Remove the upper fixing screw of the wheel

housing to permit movement.

- Drain the cooling system.

- Remove the feed and return hoses from the ex-

pansion tank.

- Remove the coolant feed and return hoses from

the radiator.

- Remove the fixing screws of the radiator to the

frame shown in the figure.

- Disengage the complete radiator and the electric

fan.

Expansion tank

To remove the expansion tank, proceed as follows:

- Drain the cooling system.


- Disconnect the expansion tank pipes.


CHAS - 267

- Remove it from the retaining seat.

Handles and top side fairings


- Remove the rear central cover.


- Working from both sides, undo the screw «A».

- Working from both sides, undo the three screws

«B».

- Remove the upper side fairings.


CHAS - 268

Flyscreen

- Remove the three hex. socket head screws, then

remove the windshield together with the rubber

rings.

To remove the windshield supports, proceed as

follows:

- Remove the caps and the gaskets on the two

windshield supports.

- Remove the FRONT UPPER FRAME.



- Remove the supports.

Pilot lights kit

- Remove the front handlebar cover.

- Remove the three screws shown in the figure,

then slide off the complete unit from the front han-

dlebar cover.


CHAS - 269

Battery

- Remove the elastic strap and the battery cover.

- First disconnect the negative terminal «A», then

the positive terminal «B».

- Remove the battery.


CHAS - 270

INDEX OF TOPICS

PRE-DELIVERY PRE DE

Carry out the listed tests before delivering the vehicle.

Warning - Handle fuel with care.

Aesthetic inspection

Appearance check:

- Paintwork

- Fitting of plastics

- Scratches

- Dirt

Tightening torques inspection

Lock check

- Safety locks

- Fixing screws

Safety locks

Rear shock absorber upper fixing

Rear shock absorber lower fixing

Lower front shock absorber fitting

Front wheel axle nut

Front wheel screws

Rear wheel screws

Front and rear wheel hub nut

Front and rear brake calliper clamping screws

Frame - swinging arm bolt *

Swinging arm bolt - Engine

Engine arm pin - Frame arm

Handlebar lock nut

Steering lower ring nut

Upper steering ring nut

Electrical system

• Main switch

• Lights: high-beam lights, low-beam lights, taillights (front and rear) and relevant warning lights

- Headlight adjustment according to the regulations currently in force

• Front and rear stop light buttons and relative light •Turn indicators and relative telltales

• Instrument lighting

• instruments: fuel and temperature indicator

Pre-delivery MSS Nexus 125 i.e. (2008)

PRE DE - 272

•Instrument panel lights

• Horn

• Electrical start up

• Engine stopping with emergency stop switch

• electric saddle opening buttonCAUTION

TO ENSURE MAXIMUM PERFORMANCE, THE BATTERY MUST BE CHARGED BEFORE USE.INADEQUATE CHARGING OF THE BATTERY WITH A LOW LEVEL OF ELECTROLYTE BEFOREIT IS FIRST USED SHORTENS THE LIFE OF THE BATTERY.CAUTION

WHEN INSTALLING THE BATTERY, ATTACH THE POSITIVE LEAD FIRST AND THEN THE NEG-ATIVE ONE.WARNING

BATTERY ELECTROLYTE IS TOXIC AND IT MAY CAUSE SERIOUS BURNS. IT CONTAINS SUL-PHURIC ACID. AVOID CONTACT WITH YOUR EYES, SKIN AND CLOTHING.IN CASE OF CONTACT WITH YOUR EYES OR SKIN, RINSE WITH ABUNDANT WATER FORABOUT 15 MINUTES AND SEEK IMMEDIATE MEDICAL ATTENTION.IF IT ACCIDENTALLY SWALLOWED, IMMEDIATELY DRINK LARGE QUANTITIES OF WATER ORVEGETABLE OIL. SEEK IMMEDIATE MEDICAL ATTENTION.BATTERIES PRODUCE EXPLOSIVE GASES; KEEP THEM AWAY FROM NAKED FLAMES,SPARKS AND CIGARETTES. IF THE BATTERY IS CHARGED IN A CLOSED PLACE, TAKE CARETO ENSURE ADEQUATE VENTILATION. ALWAYS PROTECT YOUR EYES WHEN WORKINGCLOSE TO BATTERIES.KEEP OUT OF THE REACH OF CHILDRENCAUTION

NEVER USE FUSES WITH A CAPACITY HIGHER THAN THAT RECOMMENDED. USING A FUSEOF UNSUITABLE RATING MAY SERIOUSLY DAMAGE THE VEHICLE OR EVEN CAUSE A FIRE.

Levels check

Level check:

- Hydraulic brake system liquid level.

- Rear hub oil level

- Engine coolant level

- Engine oil level

Road test

Test ride

- Cold start

- Instrument operations

- Response to the throttle control

- Stability on acceleration and braking

- Rear and front brake efficiency

- Rear and front suspension efficiency

MSS Nexus 125 i.e. (2008) Pre-delivery

PRE DE - 273

- Abnormal noise

Static test

Static control after the test ride:

• Hot engine restart

• Minimum seal (turning the handlebar)

• Uniform steering rotation

• Possible losses

• electric radiator fan operationCAUTION

CHECK AND ADJUST TYRE PRESSURE WITH TYRES AT AMBIENT TEMPERATURE.CAUTION

NEVER EXCEED THE RECOMMENDED INFLATION PRESSURES OR TYRES MAY BURST.

Functional inspection

Functional Checks:

• Hydraulic braking system: lever travel

• Clutch: proper functioning check

• Engine: proper general functioning and no abnormal noise check

• Other: papers check, chassis and engine number check, tools and equipment, licence plate fitting,

lock check, tyre pressure check, rear-view mirror and any accessory fitting

Pre-delivery MSS Nexus 125 i.e. (2008)

PRE DE - 274

INDEX OF TOPICS

TIME TIME

This section is dedicated to the time necessary to carry out repairs.

For each operation, the description, code and time envisages are specified.

Engine

ENGINECode Action Duration

1 001001 Engine from chassis - Removal andrefit.

2 001127 Engine - Complete service

Time MSS Nexus 125 i.e. (2008)

TIME - 276

Crankcase

CRANKCASECode Action Duration

1 001133 Engine crankcase - Replacement2 001099 Flywheel-side oil seal - Replacement3 001100 Clutch-side oil seal - Replacement4 001124 Lubrication by pass - Replacement5 001153 Crankcase halves gasket - Replace-

ment

MSS Nexus 125 i.e. (2008) Time

TIME - 277

Crankshaft

CRANKSHAFTCode Action Duration

1 001117 Crankshaft - Replacement


TIME - 278

Cylinder assy.

CYLINDER ASSEMBLYCode Action Duration

1 001002 Cylinder / Piston - Replacement2 001154 Pistonsrings-pin assembly - Service3 001176 Rings / Pin - Replacement4 000212 Cylinder gasket - Repl.


TIME - 279

Cylinder head assy.

HEAD ASSEMBLYCode Action Duration

1 001057 Thermostat - Replacement2 007012 Coolant bleed valve - Replacement3 000235 Coolant temperature sensor - Repl.4 001056 Head gasket - change5 001045 Valves - Replacement6 001049 Valves - adjust7 001202 Residual stroke - Check8 001203 Calibrated washer - Replacement


TIME - 280

Rocker arms support assy.

ROCKERS MOUNTING UNITCode Action Duration

1 001148 Rockers valves - Replacement2 001126 Head - Replacement3 001044 Camshaft - Replacement4 140021 Camshaft timing system pulley - Re-

plac


TIME - 281

Cylinder head cover

HEAD COVERCode Action Duration

1 001089 Head cover - Replacement2 001093 Spark plug - Replacement3 001088 Head cover gasket - Replacement4 001074 Oil vapour recovery pipe - Replace-

ment5 001159 Oil vapour recovery tank - Service


TIME - 282

Flywheel cover

FLYWHEEL COVERCode Action Duration

1 001150 Flywheel cover gasket - change2 001160 Oil pressure sensor - change3 001123 Oil filter -Replacement4 001102 Net oil filter - change / Cleaning5 003064 Engine oil - change6 001087 Flywheel cover - Replacement


TIME - 283

Driven pulley

DRIVEN PULLEYCode Action Duration

1 001012 Driven pulley - overhaul2 001022 Clutch - Replacement3 001110 Driven pulley- Replacement4 001155 Clutch housing - Replacement


TIME - 284

Oil pump

OIL PUMPCode Action Duration

1 001129 Chain tensioner - Service and Re-placement

2 001125 Chain guide pads - Replacement3 001122 Oil pump chain - Replacement4 001172 Chain cover flap - change5 001130 Oil sump - change6 001042 Oil pump - overhaul7 001112 Oil pump - change8 001051 Belt/Timing chain - Change


TIME - 285

Final gear assy.

FINAL REDUCTION GEARCode Action Duration

1 002031 Rear wheel hub bearings - Replace-ment

2 003065 Gear box oil - Replacement3 004180 Reduction gear pipe - replace4 004125 Rear wheel axle - Replacement5 001179 Hub drive shaft - replacement6 001156 Gear reduction unit cover - Replace-

ment


TIME - 286

Driving pulley

DRIVING PULLEYCode Action Duration

1 001177 CVT rollers / sliders - Replacement2 001086 Driving half-pulley - Replacement3 001011 Drive belt - Replacement4 001066 Driving pulley - Removal and refitting5 001006 Driving pulley - Service


TIME - 287

Transmission cover

TRANSMISSION COVERCode Action Duration

1 001135 Transmission cover bearing - Re-placement

2 001096 Transmission crankcase cover - Re-placement

3 001131 Transmission air intake - Replace-ment

4 001145 Belt crankcase - Replacement5 001204 CVT Filter - Replacement


TIME - 288

Water pump

WATER PUMPCode Action Duration

1 007009 Head-pump by-pass rubber sleeve -Replacement

2 001113 Water pump - Replacement3 005154 Power cable harness - Replacement


TIME - 289

Starter motor

ELECTRIC STARTERCode Action Duration

1 001020 Starter motor - Replacement2 001017 Start-up pinion - Replacement3 001151 Starter driven gearing - Replacement


TIME - 290

Flywheel magneto

MAGNETO FLYWHEELCode Action Duration

1 001173 Rotor - Replacement2 001058 Complete flywheel - change3 001067 Stator - Removal and Refitting4 001104 Start-up freewheel - Replacement


TIME - 291

Butterfly valve

THROTTLE BODYCode Action Duration

1 001166 Throttle body - Replacement2 001047 Injector - Replacement3 001013 Intake manifold - change


TIME - 292

Exhaust pipe

SILENCERCode Action Duration

1 001095 Silencer heatshield - Replacement2 005138 Lambda probe - Replacement3 001092 Exhaust manifold - Replacement4 001009 Silencer - Replacement


TIME - 293

Air cleaner

AIR CLEANERCode Action Duration

1 004122 Air cleaner/ carburettor union - Re-placement

2 001014 Air filter - Replacement / cleaning3 001015 Air filter box - Replacement


TIME - 294

Frame

CHASSISCode Action Duration

1 004001 Frame - Replacement2 004146 Front chassis - Replacement


TIME - 295

Centre-stand

STANDCode Action Duration

1 004102 Side stand - Replacement2 004004 Stand - Replacement3 001053 Stand pin - Replacement4 004179 Stand bumper - Replacement


TIME - 296

Legshield spoiler

FRONT SHIELD SPOILERCode Action Duration

1 004028 Windshield glass - Replacement2 004064 Legshield - Replacement3 004149 Shield central cover - Replacement


TIME - 297

FRONT SHIELD SPOILERCode Action Duration

1 004068 Passenger handgrip - Replacement2 004053 Spoiler - Replacement3 004012 Rear fairings - Removal and refitting


TIME - 298

Side fairings

SIDE COVERSCode Action Duration

1 004105 Right side clamp - Replacement2 004011 Central chassis cover - Replacement3 004104 Left side cover - Replacement4 004013 Side/rear bumper pipes - Replace-

ment5 004143 Footrest support - Replacement6 004079 Footrest - replacement7 004015 Footrest - Removal and Refitting8 004075 Front mat - Replacement


TIME - 299

Rear cover

SHIELD BACK PLATECode Action Duration

1 004065 Shield back plate - Replacement2 004145 Glove box - Replacement


TIME - 300

Mudguard

MUDGUARDSCode Action Duration

1 003087 Wheel housing - Replacement2 004009 Rear mudguard - Replacement3 004002 Front mudguard - change4 612011 Rear mudflap - Replace


TIME - 301

Fuel tank

FUEL TANKCode Action Duration

1 004170 Tank filler neck - Replacement2 004168 Fuel tank cap - Replacement3 004005 Fuel tank - Replacement4 004073 Fuel pump - Replacement5 004137 Pump/ injector pipe - Replacement


TIME - 302

Rear shock-absorber

REAR SHOCK ABSORBERSCode Action Duration

1 003007 Rear shock absorbers - Replace-ment

2 003077 Silencer/rear shock absorber sup-port arm - Service


TIME - 303

Handlebar covers

HANDLEBAR COVERSCode Action Duration

1 004156 Glove box flap and/or support - Re-placement

2 004019 Handlebar rear section - Replace-ment

3 004018 Handlebar front section - Replace-ment

4 004035 Instrument panel - Replacement


TIME - 304

Handlebar components

REAR-VIEW MIRRORCode Action Duration

1 004066 Driving mirror - Replacement


TIME - 305

HANDLEBAR COMPONENTSCode Action Duration

1 002060 Complete throttle control - Replace-ment

2 002059 Right-hand knob - Replacement3 003001 Handlebar - Replacement4 003061 Accelerator transmission - adjust5 002063 Complete throttle transmission - Re-

placement6 002071 Left knob - Replacement7 002037 Brake lever - Replacement8 002067 Rear brake pump - Replacement9 002024 Front brake pump - Replacement10 004162 Mirror mounting and/or brake pump

fitting U-bolt - Replacement11 003059 Counterweight - Replacement12 000307 RIGHT OR LEFT CONTROL AS-

SEMBLY REPLACEMENT

Swing-arm

SWINGING ARMCode Action Duration

1 004058 Silent block - Replacement2 003081 Swinging arm support flange - Re-

placement3 001072 Engine-chassis connection swinging

arm - Replacement4 003080 Swinging arm on chassis - Replace-

ment


TIME - 306

Seat

SADDLECode Action Duration

1 004003 Saddle - Replacement


TIME - 307

Instrument panel

INSTRUMENT PANEL AND HANDLEBAR CONTROLSCode Action Duration

1 005038 Instrument panel warning light bulbs- Replacement

2 005014 Odometer - Replacement3 005082 Instrument panel cable harness - Re-

placement4 005129 Warning light group - Replacement


TIME - 308

Locks

LOCKSCode Action Duration

1 004010 Anti-theft lock - Replacement2 005072 Immobilizer aerial - Replacement3 004054 Saddle lock catch - Replacement


TIME - 309

Turn signal lights

FRONT LIGHTSCode Action Duration

1 005044 Front lights cable unit - replace2 005067 Front turn indicator bulb - Replace-

ment3 005012 Front turn indicator - Replacement4 005002 Front headlamp - Replacement5 005008 Headlight bulbs - Replacement


TIME - 310

REAR LIGHTSCode Action Duration

1 005030 Rear headlight cable unit- Replace-ment

2 005066 Rear light bulbs - Replacement3 005005 Taillight - change4 005028 Rear light assembly glass - Replace-

ment5 005068 Rear turn indicator bulb- Replace-

ment6 005091 Turn indicator glass - Replacement7 005022 Rear turning indicators - Replace-

ment8 005030 Rear headlight cable unit- Replace-

ment9 005131 number plate light support - Replace-

ment10 005031 number plate light bulb - Replace-

ment


TIME - 311

Front wheel

FRONT WHEELCode Action Duration

1 002011 Odometer movement sensor - Re-placement

2 003040 Front wheel bearings - Replacement3 004123 Front wheel - Replacement4 002041 Front brake disc - Replacement5 003038 Front wheel axle - Remov. and refitt.6 003037 Front wheel rim - Replacement7 003063 Tyre pressure - Check8 003047 Front tyre - Replacement


TIME - 312

Rear wheel

REAR WHEELCode Action Duration

1 001016 Rear wheel - Replacement2 002070 Rear brake disc - Replacement3 001071 Rear wheel rim - Replacement4 004126 Rear wheel tyre - Replacement5 003063 Tyre pressure - Check


TIME - 313

Electric devices

VOLTAGE REGULATORCode Action Duration

1 001069 HV coil - Replacement2 001094 Spark plug hood - Replacement3 005009 Voltage regulator - Replacement


TIME - 314

WIRE UNITCode Action Duration

1 005001 Electrical system - Replacement


TIME - 315

REMOTE CONTROLSCode Action Duration

1 000319 Remote control - Replac.2 005011 Starter relay - Replacement3 005007 Battery - change4 005003 Horn - Replacement


TIME - 316

Electronic controls

LIGHT SWITCHESCode Action Duration

1 005017 Stop switch - Replacement2 888126 Helmet compartment light switch - re-

placement3 005079 Side stand switch - Replacement


TIME - 317

Transmissions

TRANSMISSIONSCode Action Duration

1 002083 Saddle opening transmission - Re-placement


TIME - 318

Helmet bay

HELMET COMPARTMENTCode Action Duration

1 004142 electric socket - Replacement2 005027 Helmet compartment bulb support -

Replacement3 005046 Battery cover - change4 004016 Helmet compartment - Remov. and

Refit.


TIME - 319

Front suspension

FRONT SUSPENSIONCode Action Duration

1 003076 Fork sleeve - Replacement2 003069 Front fork oil - Replacing3 003048 Fork oil seal - Replacement4 003010 Front suspension - Service5 003051 Complete fork - Replacement6 004119 Steering Bearing / upper steering

bearing - Replacement7 003002 Steering bearing - Replacement8 003073 Steering clearance - Adjustment9 003079 Fork stem - Replacement


TIME - 320

Cooling system

COOLING SYSTEMCode Action Duration

1 007002 Water cooling radiator - Replace-ment

2 007016 Fan with support - Replacement3 007001 Expansion tank - Replacement4 007024 Expansion tank cap - Replacement5 007019 Coolant return pipe - replacement6 007013 Expansion tank / radiator connecting

hose - Replacement7 001052 Coolant and air bleed - replacement8 007022 Coolant delivery pipe - Replacement


TIME - 321

Braking system

BRAKING SYSTEMCode Action Duration

1 003070 Front brake pads / Shoes - Checkwear

2 002007 Front brake pads - Replacement3 002039 Front brake calliper - Replacement4 002040 Front brake calliper - Check5 002047 Front brake fluid and air bleed sys-

tem - Replacement6 002021 Front brake piping - Replacement7 002002 Shoes - Rear brake pads - Replace-

ment8 003071 Rear brake pads - Wear check9 002048 Rear brake calliper - Replacement10 002068 Rear brake calliper - Check11 002020 Rear brake pipes - Removal and re-

fitting12 002080 Rear brake oil bleed system -

Change


TIME - 322

Windscreen

WINDSCREENCode Action Duration

1 004028 Windshield glass - Replace


TIME - 323

Stickers

TRANSFERSCode Action Duration

1 004159 Plates / Stickers - Replacement


TIME - 324

AAir filter: 41, 261

BBattery: 63, 77, 78, 270Brake: 228, 230, 232, 233, 235, 236, 239Bulbs:

CChecks: 65Coolant: 189

EElectric: 314Engine oil: 43

FFuel: 165, 173, 265, 302Fuses: 75

HHeadlight: 48, 249Hub oil: 40

IIdentification: 8Instrument panel: 248, 308

MMaintenance: 7, 39Mirror:

OOil filter: 45

RRecommended products:

SSaddle: Shock absorbers: 224Spark plug: 39, 70Stand: 225Start-up: Suspension: 51, 52, 320

TTank: 265, 267, 302Transmission: 10, 50, 93, 107, 288Tyres: 11

VVehicle: 8, 86, 87

Gilera Nexus 125 i.e. MY 2008 (EN)

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Transcript of Gilera Nexus 125 i.e. MY 2008 (EN)