Warranty• DuraTrax® will warranty this kit for 90 days after the purchase date from defects in materials or workmanship. DuraTrax

will either repair or replace, at no charge, the incorrectly made part.• Make sure you save the receipt or invoice you were given when you bought your model! It is your proof of purchase

and we must see it before we can honor the warranty.• To return your Street Force GP for repairs covered under warranty you should send your touring car to:

Hobby Services1610 Interstate Drive

Champaign, Illinois 61822Attn: Service Department

Phone: (217) 398-0007 9:00 am - 5:00 pm Central Time M-FE-mail: hobbyservices@hobbico.com

Before Building:We want the building and operating of this vehicle to be a success, so BEFORE removing any parts from the parts bagsplease read this manual thoroughly and watch the included video to familiarize yourself with the model. If for any reasonyou think this model is not for you, return it to your dealer immediately. PLEASE NOTE: Your hobby dealer cannot accepta return on any model after assembly has begun.

© Copyright 2000 DTXZ1070 For Kit DTXC0050/DTXD50**

TM

ASSEMBLY AND OPERATION MANUAL

®

Introduction.................................................................................2Safety Precautions .....................................................................2Helpful Hints................................................................................2Stress-Tech™ Parts Guarantee...................................................2Repair Service.............................................................................2Specification & Description Changes.......................................3Screw Information ......................................................................3Required Items for Completion .................................................3Tools You Will Need....................................................................3Finishing the RTR Version.........................................................4

Air Filter Installation............................................................4Radio Set-Up ........................................................................4Body Mounting ....................................................................5

Assembly of the Pre-Built Version............................................6Preparing the Radio System ..............................................6Radio Set-Up ........................................................................6Air Filter Installation..........................................................10Body Mounting ..................................................................10

Carburetor Settings ..................................................................11Running the Engine..................................................................11Breaking-In the Engine ............................................................12Engine Maintenance .................................................................12Performance Tuning .................................................................13Maintenance Tips......................................................................14Engine Trouble Shooting .........................................................15

Thank you for purchasing the DuraTrax Street Force GP.This manual contains the instructions you need to build,operate and maintain your new nitro R/C touring car. Readover this manual thoroughly before building or operating theStreet Force GP.

When the safety precautions are followed, the Street ForceGP will provide years of enjoyment. Use care and goodsense at all times when operating this radio controlledtouring car. Failure to use this vehicle in a safe, sensiblemanner can result in injury or damage to property. You andyou alone must insure that the instructions are carefullyfollowed and all safety precautions are obeyed.

• Do not operate the Street Force GP near people.Spectators should be behind the driver or at a safedistance away from the vehicle.

• The engine and exhaust produces quite a bit of noise. Ifyou are disturbed by the amount of noise this touring carproduces, wear ear protection such as earplugs. Do notrun this vehicle when or where it can disturb others.

• The engine and exhaust can become very hot. Avoidtouching any of these parts during use and until theyhave cooled down.

• Model engine fuel is poisonous. Make sure you read andfollow all of the precautions on the fuel container. Keepfuel out of the reach of children.

• Model engine fuel is flammable and when ignited has aflame that is difficult to see. Avoid sparks, flames,smoking, or any other ignition source when fuel is near.

• The engine emits carbon dioxide just like real cars. Donot operate this model indoors.

• Before turning on the transmitter, make sure that no oneelse is on your frequency.

• Avoid working over a deep pile carpet. If you drop a smallpart or screw, it will be difficult to find.

• Place a mat or towel over your work surface. This willprevent parts from rolling off and will protect the worksurface.

• Avoid running the touring car in cold weather. The plasticand metal parts can become brittle at low temperatures.In addition, grease and oil become thick, causingpremature wear and poor performance.

• Test fit all parts before attaching them permanently.

We have engineered the Street Force GP to take the highspeed abuse that makes R/C cars fun. We are so confidentof the quality and durability of the Stress-Tech™ plastic partsthat we will replace any Stress-Tech plastic part you breakduring the first 6 months you own the touring car. Just sendin the part to us and we will send you a Free replacement.Please see the Street Force GP parts list for the itemscovered under the Stress-Tech guarantee.

To receive your free replacement part please send thefollowing to the Hobby Services address listed on the coverof this manual:

• The broken part must be included.• The part number and description of the broken part.• Dated copy of your invoice or purchase receipt.• Your name, phone number and shipping address.

Repair service is available anytime. • After the 90 day warranty, you can still have your Street

Force GP repaired for a small charge by the experts atDuraTrax’s authorized repair facility, Hobby Services, atthe address listed on the front page of this manual.

REPAIR SERVICE

STRESS-TECH™ PARTS GUARANTEE

HELPFUL HINTS

SAFETY PRECAUTIONS

INTRODUCTION

TABLE OF CONTENTS

2

To speed up the repair process, please follow theinstructions listed below.

1. Under most circumstances return the ENTIRE system:touring car and radio. The exception would be sending ina Stress-Tech part. See the instructions under Stress-Tech Guarantee.

2. Make sure the transmitter is turned off, all batteries areremoved and fuel is drained from the tank.

3. Send written instructions which include: a list of all itemsreturned, a THOROUGH explanation of the problem, theservice needed and your phone number during the day. Ifyou expect the repair to be covered under warranty, besure to include a proof of date of purchase (your storereceipt or purchase invoice).

4. Also be sure to include your full return address.

All pictures, descriptions and specifications found in thisinstruction manual are subject to change without notice.DuraTrax maintains no responsibility for inadvertent errorsin this manual.

Do not use too much force when tightening self-tappingscrews into plastic. Overtightening will cause the threads inthe plastic to strip. We recommend that you stop turning aself-tapping screw when you feel some resistance as thehead of the screw comes in contact with the plastic. Avoidusing powered screwdrivers when assembling this kit. Theytend to overtighten the screws. Do not use thread lockingcompound on any self-tapping screws. The thread lockingcompound may damage the plastic. IMPORTANT: Usethread lock on any fastener that is threaded into metal orfastened with a nut. Vibration from the engine will cause thescrews to loosen if thread locking compound is not used.

To operate the Street Force GP these items are required:

• Fuel (DuraTrax Red Alert fuel - DTXP0520)• Air Filter Oil• Glow plug wrench (DTXR1170)• It is also helpful to have a couple of extra glow plugs

on hand (O.S. #A3 plug - OSMG2690)• Hobby knife (HCAR0105), #11 blades (HCAR0211)

The Nitro Starter Pack from Duratrax (DTXP0200)includes fuel, deluxe wrench, fuel bottle, rechargeableglowplug starter and an O.S. A3 glow plug.

For the Pre-Built version of the Street Force GP, you willalso need:

• 2-channel radio with (2) standard servos (FUTJ20**).• (12) “AA” batteries - (4) for the receiver and (8) for

the transmitter.• Small bottle of thread locking compound (GPMR6060).

To assemble the Pre-built version (DTXC0050), you willneed the following tools:

• Phillips head screwdriver (DTXR0122)• Needle-nose pliers (DTXR0300)• Hobby knife (HCAR0105), #11 blades (HCAR0211)

TOOLS YOU WILL NEED

REQUIRED ITEMS FOR COMPLETION

3mm

14mm

M3x14 Screw

3mm

14mm

M3x14Self-Tapping

Screw

SCREW INFORMATION

SPECIFICATION & DESCRIPTION CHANGES

3

❏ 1. Install the air filter onto the carburetor. Using the included tie-strap, secure the air filter to thecarburetor. Cut off any excess portion of the tie-strapto avoid interference.

❏ 2. Remove the twist-tie from around the receiverantenna wire. Run the length of the antenna wirethrough your fingers to help straighten the wire out,this will make it easier to get the wire through theantenna tube. Slide the antenna wire through theantenna tube. Press the antenna tube into the antennamount molded into the top of the radio plate.

❏ 3. Frequently, there will be leftover wire protrudingfrom the antenna tube Do not cut or coil theantenna! Cut two pieces of fuel tubing 1/8" long andslide them over the outside of the antenna tube andwire. This is to help hold the excess antenna onto thetube on and avoid getting the antenna wire cut in a rollover. Note the placement of the fuel tubing on theantenna tube.

❏ 4. It may be necessary to loosen the radio plate toremove the receiver battery holder. Install 4 "AA"batteries (included) into the receiver battery holder inthe configuration molded into the battery holder. Installthe receiver battery back into the receiver batteryholder as shown. Make sure to re-tighten the radioplate screws once the receiver battery is in place.

RADIO SET-UP

AIR FILTER INSTALLATION

4

FINISHING THE STREET FORCE GP TOURING CAR RTR VERSION (DTXD50**)

❏ 5. Plug the male end of the wire from the receiver(RX) battery into the female end from the on/off switch.

❏ 6. Remove the transmitter antenna from the holderand screw it into the hole on top of the transmitter.

❏ 7. Slide open the battery door on the bottom of thetransmitter and remove the transmitter battery holder.Place 8 "AA" batteries (included) into the holder in theconfiguration molded into the plastic on the batteryholder. Re-install the transmitter battery holder into thetransmitter and re-install the battery door.

❏ 8. Turn on the transmitter (see photo with step 5).The green light should light up. If there is no light on,turn the transmitter off and check to ensure that thebattery holder is making contact with the copper

contact on the inside of the battery compartment.Make sure the batteries are installed correctly. Turnthe transmitter on and check for the green indicatorlight. If the green light appears, turn off the transmitter.

❏ 9. Raise the body posts to the upright position. Noticethere is a molded pin that fits into a hole in the shocktower. This is to keep the body posts from swivelingduring running. Tighten the screws in the body posts,making sure that the posts pull tight against the shocktowers. You will have to remove the screws in the tops ofthe front shocks to get to the front body mount screws.

❏ 10. Remove the protective plastic from the outsideof the body and apply the decals if desired.

❏ 11. Remove the body clips from the parts bag. Onthe front body posts place a body clip in the bottomhole of each post. On the rear body posts place a bodyclip in the third hole from the bottom in each post. Placethe body onto the body mounts. On each body postplace a body clip to secure the body onto the chassis.The excess body post can be trimmed off if desired.

You are ready to go! Watch the video one moretime and turn to page 11 for performance andmaintenance tips.

BODY CLIP

BODY MOUNTING

5

❏ 1. Install the “AA” batteries in the transmitter and thereceiver holders.

❏ 2. Extend the transmitter antenna.

❏ 3. Connect the steering servo, throttle servo andreceiver battery to the receiver.

❏ 4. Extend the receiver antenna.

❏ 5. Adjust the servo trims of the transmitter to theneutral position.

❏ 6. Switch on the transmitter.

❏ 7. Switch on the receiver.

❏ 8. Operate the steering and throttle control. Makesure the servo arms move in proportion to themovement of the steering wheel and throttle trigger.

❏ 9. Switch off the receiver, then the transmitter.

❏ 1. Remove the Street Force GP Touring Car fromthe box.

❏ 2. Remove the radio plate from the chassis byremoving the 7 screws as indicated in the above photos.

❏ 3. Install the on/off switch into the slot in front of thefuel tank. Install the switch up through the bottom ofthe radio plate, then install the face plate onto the topof the radio plate. Re-install the two screws throughthe face plate and into the switch to secure it to theradio plate. Be careful to put the switch plate oncorrectly with respect to on and off switch positions.

RADIO SET-UP

PREPARING THE RADIO SYSTEM

6

ASSEMBLY OF THE STREET FORCE GP TOURING CAR PRE-BUILT VERSION (DTXC0050)

Servo Arm

SteeringServoThrottle

Servo

ReceiverBatteryHolder

4-AA Batteries1 Antenna4

Receiver3

ReceiverSwitch

7

Transmitter

5

6

8-AA Batteries1

Antenna2

8

Before installing the radiosystem in the pre-builtDuraTrax Street Force GPread the manufacturer’sinstruction manual andfollow the instructionsshown below.

❏ 4. Install the throttle/brake servo into the slot next tothe fuel tank. Place the two servo mount blocks ontothe bottom of the radio plate. Then install the four3x10mm self-tapping screws through the servo into theservo mounts. Route the servo wire through the slottedhole between the servo and the receiver battery holder.

❏ 5. Reinstall the radio plate onto the chassis. Makesure to reinstall the washer between the steeringbellcrank and the radio plate.

❏ 6. Install the two servo mounting posts onto thesteering servo as shown (note location of servo spline).Note that the hole in the bottom of the servo mountingposts are off-center. Install the posts with the hole inthe bottom of the post as shown in the photo. This is tohelp prevent the servo from hitting the center belt.

❏ 7. Install the steering servo onto the chassis fromunderneath using a 3x10mm flat head self-tappingscrew in the front hole which is countersunk and a3x10mm round head self-tapping screw in the slottedrear mounting hole. Route the steering servo wirethrough the slotted hole between the steering servoand the receiver battery holder.

❏ 8. Install the receiver using the included double-sided tape onto the top of the radio plate as shown.Run the length of the antenna wire through your fingers

7

to help straighten the wire out, this will make it easier toget the wire through the antenna tube. Slide theantenna wire through the antenna tube. Press theantenna tube into the antenna mount molded into thetop of the radio plate.

❏ 9. Frequently, there will be leftover wire protrudingfrom the antenna tube Do not cut or coil theantenna! Cut two pieces of fuel tubing 1/8" long andslide them over the outside of the antenna tube andwire. This is to help hold the excess antenna onto thetube on and avoid getting the antenna wire cut in a rollover. Note the placement of the fuel tubing on theantenna tube.

❏ 10. Plug the switch wire into the battery (batt) slot onthe receiver. Plug the steering servo and throttle servowires into the receiver. See your radio instructions todetermine which channel is steering and which is throttle.

❏ 11. Install the receiver battery into the receiverbattery holder as shown. It may be necessary toloosen the radio plate slightly to fit the receiver batteryin. Make sure to re-tighten the radio plate screws oncethe receiver battery is in.

❏ 12. Thread the ball stud into the correct servo horn(included) for your steering servo as shown.

❏ 13. Thread the two ball ends onto the steel rod. Thereshould be 19mm or 3/4" between the two ball ends.

8

❏ 14. Snap one end of the rod onto the steering servohorn. Snap the other end onto the steering arm. Turnthe transmitter on and center the steering trims. Installthe steering servo horn onto the steering servo asshown. Then turn the transmitter and receiver off.

❏ 15. Install the rod connector into the hole farthestaway from the center on the short servo horn (included).Note: This hole is slightly enlarged. Place the smallmetal washer and 2mm nut onto the bottom of the rodconnector. Make sure not to over-tighten the nut, the rodconnector must swivel freely. Apply a small amount ofthread lock onto the nut to prevent it from falling offduring running.

❏ 16. Locate the small rod with a z-bend at one end.Install the z-bend end of the rod into the lower hole ofthe throttle arm on the carburetor. Turn the transmitter

on again and center the throttle trim on it. Install a setscrew into one of the wheel collars. NOTE: Only threadthe set screw in slightly so that the wheel collar willslide over the throttle linkage rod. Place the metalwheel collar and the throttle linkage spring onto thethrottle rod (Do not tighten the wheel collar yet). Installthe throttle servo horn onto the throttle servo as shown.

❏ 17. Make sure the carburetor is at the idle setting(refer to the throttle stop screw, page 11), then installthe second wheel collar onto the end of the throttlelinkage rod. The wheel collar should slide up againstthe throttle linkage rod connector as shown.

❏ 18. Slide the first wheel collar against the throttlelinkage spring, slightly compressing the spring. Tightenthe set screw in the wheel collar. You should apply asmall amount of thread lock to the set screws inthe wheel collars to prevent them from looseningduring running.

❏ 19. Lift the throttle linkage servo horn off of theservo. Install the remaining z-bend wire from thebottom into the hole farthest from the center of theservo horn. Note: This hole is slightly enlarged. Slidethe threaded end of the brake linkage rod through thebrake lever.

Rod Connector

Rod Connector

9

❏ 20. Slide the pre-cut 5mm (1/4") piece of fuel tubingonto the threaded end of the brake linkage rod. Thefuel tubing should slide all the way up against thebrake lever. Then thread the quick tune brake adjusteronto the brake linkage rod. Note: The transmittershould still be on for this step. Thread the quick tunebrake adjuster on until it almost touches the pre-cutpiece of fuel tubing. Note: At this position the carshould roll freely. Move the transmitter trigger to applythe brakes and try to gently move the vehicle. If the carrolls freely the quick tune brake adjuster should bethreaded on farther. If the car does not move then thelinkage is set up correctly. Install the servo horn screwinto the throttle servo.

❏ 21. Install the air filter onto the carburetor. Using the included tie-strap, secure the air filter to thecarburetor. Cut off any excess portion of the tie-strapto avoid interference.

❏ 22. Raise the body posts to the upright position.Notice there is a molded pin that fits into a hole in theshock tower. This is to keep the body posts fromswiveling during running. Tighten the screws in thebody posts, making sure that the posts pull tightagainst the shock towers. You will have to remove thescrews in the tops of the front shocks to get to the frontbody mount screws.

❏ 23. Remove the protective plastic from the outsideof the body and apply the decals if desired.

❏ 24. Remove the body clips from the parts bag. Onthe front body posts place a body clip in the bottomhole of each post. On the rear body posts place a bodyclip in the third hole from the bottom in each post. Placethe body onto the body mounts. On each body postplace a body clip to secure the body onto the chassis.The excess body post can be trimmed off if desired.

BODY CLIP

BODY MOUNTING

AIR FILTER INSTALLATION

10

The High-Speed NeedleThe “high-speed” needle is sticking up from the side ofthe carb. It is located in the brass housing, just abovethe fuel inlet. It controls the fuel-to-air mixture of thecarb. The needle is pre-set for break-in from thefactory at 2-1/2 turns out from the fully closed positionof the carb. Once the engine is broken-in, the high-speed needle would typically run from 2 to 2-1/2 turnsout from closed, depending on the weather, humidityand altitude above sea level. To richen turn the needlecounterclockwise, to lean turn the needle clockwise.

The Low-Speed NeedleThe “low-speed” needle is the screw in the carb body,opposite the throttle arm. It controls the fuel to airmixture at low throttle settings. There is a simple way ofadjusting the low-speed needle correctly called the“pinch test.” With the engine at idle, pinch the fuel lineand listen to how the engine speeds up or slows down.If the engine increases its speed for about 2 or 3seconds and then loses RPM, the needle is setcorrectly. If the engine loses RPM quickly, it is set toolean and the low-speed needle needs to be opened(counterclockwise) to richen the mixture. Pinch againto check the mixture. If the engine takes longer than 4seconds to slow down, lean (clockwise) the low-speedneedle and then pinch again to check the mixture.

The Throttle Stop ScrewOn the front of the carburetor, there is a black screw.This is called the throttle stop screw. This increases ordecreases the idle RPM without changing the fuel-toair-mixture. You should see an openning ofapproximately 1.5mm (between 1/32” and 1/16”)between the carb body and the carb barrel when thethrottle is pushed closed.

Before running the engine, read everything in thismanual concerning engines and watch the enginevideo that came with this kit.

There are several simple steps to starting the engine:

1. Install a glow plug if one is not in your engine. Thisthreads into the top of the cylinder head.

2. Fill the tank almost to the top. Leave a little air at thetop of the tank.

3. Prime the engine by turning the flywheel on theengine. Watch the fuel go through the line andwhen it gets to the carburetor, turn the flywheel onemore full revolution.

4. Open the high speed needle valve exactly 2-1/2turns out (counterclockwise) from fully closed. Becareful not to overtighten the high speed needle.When you feel some resistance, stop turning theneedle. The high-speed needle is sticking upfrom the carburetor inside the brass housing.All of the carburetor settings are adjusted with a flatbladed screwdriver. If you have previously run thetouring car, keep the same needle valve setting thatyou used on your last run.

5. Start the engine by pulling the recoil - Use short,quick pulls. DO NOT pull the recoil starter’s string tothe end. You only need 10 to 12 inches of pull tostart the engine.

If the engine does not start after several pulls,sometimes it is helpful to start the engine at aroundhalf throttle. Have a friend pull back on the throttlesome while you start the engine. This may be anindicator that the low speed needle setting needs to beadjusted. When the engine starts, immediately returnthe throttle to idle. If this is not done the engine can

RUNNING THE ENGINE

1/32" TO 1/16" GAP

CARBURETOR SETTINGS

11

over-rev and cause engine damage. If the engine isdifficult to turn over with the recoil starter,especially if it is brand new, loosen the glow pluga half turn before starting the engine. This allowssome compression to escape, but the engine willstill start. Make sure you tighten the glow plugafter the engine starts. If the recoil starter is stilldifficult to pull, the engine is flooded – there is toomuch fuel inside the engine. Remove the glow plugand air cleaner, then turn the engine upside down andpull the recoil 5 or 6 times. This will clear the engine offuel, and you will notice the recoil pulls easier. Replacethe glow plug and repeat the starting procedure.

FuelsUse fuels that are specially formulated for car andtruck engines. DuraTrax Red Alert fuel is speciallyformulated for R/C car engines like the Velocity .15.

How To Stop Your EngineYou may have been wondering how to stop theengine. All you have to do is pinch the fuel line thatruns to the carburetor and from the bottom of the fueltank. Pinching this will restrict the fuel flow and theengine will quit within a few seconds. You can alsotouch the flywheel with the tip of your shoe through thehole in the bottom of the chassis.

To insure long life and good performance from yourVelocity .15 engine, you MUST break-in the engine.The break-in period is critical for long life of the internalparts of the engine. This should be done over the first5 or 6 tanks of fuel. Be sure to watch the engine tuningvideo that came with this kit.

Some Things To Remember During Break-In:1. Run with the body off. This will keep the engine cooler.

2. Keep the air cleaner on at ALL times.

3. Run on a smooth, hard surface. An empty parkinglot is perfect.

4. Use the same fuel that you will use for normal running.

5. Resist the urge to accelerate and decelerate thetouring car quickly.

6. Break-in puts stress on the glow plug and you canburn it out during break-in. Make sure you have anextra plug or two on hand.

7. Do NOT overheat the engine. You can check thehead temperature by using one of the temperaturegauges that are available.

The First TankYour first tank of fuel should be running the touring carat a very rich high-speed needle valve setting. Thisallows the fuel to carry as much oil as possible into theengine to lubricate the internal parts during the break-in.

1. Open the needle valve 2-1/2 turns from fullyclosed (counterclockwise). This is factory setalready, but check it to make sure. When closingthe high-speed needle, close the needle until youfeel some resistance. DO NOT overtighten or youwill damage the engine.

2. Start the engine.

3. Once the engine is started, open the high-speedneedle valve around 1/8 turn at a time, finding thesetting where the engine just barely runs. This maytake a few times adjusting the needle, running thetouring car away from you and back, then adjustingthe needle. The touring car will perform sluggishlyand stall from time to time - that is normal.

4. Run the touring car back and forth at medium speeds,slowly accelerating and decelerating the touring car,until the tank is almost out of fuel. Do not allow thetank to run out of fuel. This leans out the engineand can cause overheating.

5. Stop the engine and allow the engine to cool beforethe second tank. This normally takes around 10minutes (See How To Stop Your Engine).

Tanks 2-6 Turn in the needle valve (clockwise) around 1/12 turnfrom the previous setting. Run the touring car backand forth. You should notice that the touring car willperform better during each run. Stop the touring carperiodically to check for overheating. If it is too hot,stop the engine. Wait for it to cool, then open up theneedle valve and restart. After the 6th tank, you shouldbe near to the peak performance of the engine.

Ten Ways To Ensure A Long Life From Your Engine:

1. Keep your engine clean. Dirt will act as insulationon an engine. It will not be able to shed heat aseasily. Use a good air filter to keep dirt out of yourengine and clean it often.

2. Do not over-lean your engine.

3. Do not run your engine with little or no load. Don’tthrottle up the engine to full throttle when thewheels are not in contact with the ground.

ENGINE MAINTENANCE

BREAKING-IN THE ENGINE

12

4. Do not overheat the engine. This goes along withkeeping it clean and not over-leaning the engine.

5. Do not use a fuel with a low oil content. Make sureyou use a fuel from a reputable manufacturer,such as DuraTrax Red Alert.

6. Avoid using old fuels in the engine. Always run all ofthe fuel out of the engine. After running for the day,use an after-run oil and work it into the engine byturning the flywheel or pulling the engine recoil slowly.

7. Do not use a fuel with a nitromethane (often callednitro) content over 20%.

8. Do not scratch the piston or cylinder sleeve. Avoidjamming something into the exhaust port whenremoving or re-installing the clutch or flywheel.Use a special tool called a crankshaft locking tool,which is installed in the glow plug hole.

9. Do not use silicone sealer on the engine joints.Silicone sealer contains acetic acid, which iscorrosive if it gets inside your engine.

10. Do not allow any water inside the engine. Thissounds easy, but temperature changes can causecondensation inside the engine. This is a goodreason to use an after-run oil. Store your engineinside the house, not in a garage or shed wherethere will be temperature extremes.

If you are having problems with your engine consultthe engine troubleshooting flow chart on page 19.The following are some potential problems.

Glow PlugThe glow plug is an item that will wear out and needreplacement from time to time. It is a good idea toremove the glow plug before your first run, heat it andsee how well it glows. You should see a bright orangeglow from the filament. If a coil or two will not glow orthe plug will not glow at all, replace the plug. If theengine quits when you remove the glow starter, theplug might need to be changed, although this may bebecause you are running too rich and need to screw inyour high-speed needle some. Look at the glow plugwhen you are running the engine. If you see somebubbles coming from around the plug, replace theglow plug (copper) gasket, or both the plug andgasket. The only real way to test a glow plug is toreplace it. Make sure you have a spare plug or two onhand every time that you run the Street Force GP.

FuelFuel can go bad. The main ingredient in model fuel ismethanol, which is basically an alcohol. Alcohols canabsorb water out of the air, so keep your fuel jugcapped at all times. Store your fuel out of the sunlightand in a cool place. Bad fuel is one of the most difficultproblems to diagnose in engines. If you have triedeverything you can think of to remedy an engine thatis not running correctly, try using some fresh fuel.Fuel line is susceptible to pinhole leaks. You cannot seethe hole in the fuel line, but if you see air bubbles in theline going to the carburetor, replace the fuel line. Anothersymptom of a leak in the fuel line is a surging engine. Theproperly tuned engine will surge when the air bubbles hitthe carb. It is basically leaning out the mixture.To keep dirt out of the engine, use an inline fuel filteron the fuel line running from the fuel tank to thecarburetor. Dirt can get caught in the needle seat andcause an inconsistent running engine. If you suspectthat some dirt has lodged itself in the carb, remove theneedles and clean the carb with denatured alcohol orfuel. It can help to use compressed air to blow out thefuel passages as well. Dirt can get into your carburetorand engine through the air filter. Ensure that your aircleaner has a good seal to the top of the carb.Periodically wash the air cleaner foam element and re-oil the filter. Any air cleaner that has a torn element ora bad seal should be replaced immediately.

OverheatingOne of the worst things you can do to your engine isoverheat it. The oils that lubricate the engine arecarried in the fuel. If your engine is set too lean, therewill not be enough oil in the engine to lubricate theinternal parts. This will cause premature wear in theengine and cause damage.

Toe-In/Toe-Out: This refers to the angle of the front tireswhen viewed from above when the suspension armsare level. If the fronts of the tires angle in, it is called“toe-in” and if the fronts of the tires angle out, it is called“toe-out.” This is adjusted by lengthening or shorteningthe steering rods - the rods that run between the fronthub and the servo saver. Normally a small amount oftoe-in is used to make the touring car track straight athigh speed. Too much toe-in will make the touring cardifficult to turn as well as reduce the overall top speedbecause of tire scrub. Sometimes a small amount oftoe-out will be used to help the steering. As a generalrule use a small amount of toe-in.

PERFORMANCE TUNING

13

Camber: Camber is the angle of the tops of the tireswhen viewed from the front. Negative camber is whenthe tops of the tires are angled towards the center ofthe touring car. Positive camber is where the tops ofthe tires are angled away from the center of the touringcar. Positive camber is very rarely used, if ever. Asmall amount of rear negative camber is helpful toincrease traction in the rear. Negative camber at thefront will increase stability. Camber adjustments canbe made on the Street Force GP by turning the“camber rods,” which are the upper links on thesuspension. Lengthening the camber rod will addpositive camber and shortening the camber rod willadd negative camber.

Shocks: Changes in shock oils, springs, and pre-loadon the springs can dramatically change the way thecar handles. A thicker shock oil will make the touringcar turn faster but reduces overall traction andhandling over bumpy surfaces. Thinner oil willincrease traction at the expense of steering responseand the car will tend to roll more. In general, shock oilsbetween 60 and 90 weight will be best for your touringcar. You should experiment some to see what oilswork best for your track and driving style. Shocksprings affect the rate that the suspension reboundsfrom a bump. Pre-load on the springs means that thesprings are already compressed some so that thesuspension will rebound faster. Sometimes you willwant to pre-load one side when the track has turns allor mostly in one direction, for instance an oval track. Itwill also increase the ride height.

Before Each Run• Check for loosened screws on the touring car.

Engine vibration will loosen some of the screws,particularly in the engine mount area. Use threadlock on screws that thread into metal parts or use ametal nut.

• Inspect the air cleaner for a torn or damagedelement. Also look for dirt in the air cleaner elementand wash it if necessary.

• Check the suspension and drive train for binding.

• Inspect all of the wires for damage. Also check theconnectors to make sure all of them are tight and inthe proper place.

• Check the fuel tank and fuel lines for leaks.

• Before starting the engine, turn on the radio and makesure the servos move easily and in the right direction.

• Before running always check the condition of yourradio system batteries and replace/recharge ifnecessary.

After Each Run• Drain the fuel tank of any leftover fuel. DO NOT

return it to your fuel jug.• Put some after-run oil in the carb and turn the

flywheel several times to work the oil into theengine. This will protect the engine from rusting,especially when stored for a long period of time.

• Check again for loosened screws.• CLEAN the touring car. Wipe off any oils that have

collected on the chassis, engine end exhaust. Oilswill attract dirt on the next run.

MAINTENANCE TIPS

14

0" 1" 2" 3" 4" 5" 6" 7"

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180

Inch Scale

Metric Scale (mm)

Metric Conversions1/64" = .4 mm1/32" = .8 mm1/16" = 1.6 mm3/32" = 2.4 mm

1/8" = 3.2 mm5/32" = 4.0 mm3/16" = 4.8 mm

1/4" = 6.4 mm3/8" = 9.5 mm1/2" = 12.7 mm5/8" = 15.9 mm3/4" = 19.0 mm

1" = 25.4 mm2" = 50.8 mm3" = 76.2 mm

6" = 152.4 mm12" = 304.8 mm18" = 457.2 mm21" = 533.4 mm24" = 609.6 mm30" = 762.0 mm36" = 914.4 mm

15

ENGINE TROUBLESHOOTINGThe engine starts

Does the engineturn over easily?

Does it runcontinuously?

Is fuel getting tothe engine?

Check for clogging inthe carburetor or fuel

line. Press theprimer pump and

check for fuelspraying out of the

fuel line. If so,replace the fuel line.

Is fuel in the fuel line?

Is the glow plugred hot?

Check the high speed needlesetting and prime the engine.

Is foreign matterclogging the fueltank or fuel line?

Is the battery forthe glow plugclip charged?

It should beready to go.

Is the highspeed needlesetting 2 to

2-1/2 turns outfrom closed (ifthe engine isbroken-in?)

Try starting theengine again.

NO

NO

NO

NO

YES

YES

YES

YES

YES

Does the enginequit when the

glow plug clip isremoved?

YESYESClear the engineof fuel.

NO

Reset the highspeed needle.

YES

NO

Replace theglow plug.

Check that thepressure line is

connected to themuffler. The fuel

may be bad.

The engine does not start

NODoes the engineturn over easilywith the glow

plug removed?

The engine maybe flooded.

Clear the engineof fuel.

YES

Check thatnothing is

caught in theengine. Check

that the thepull starteroperatessmoothly.

NO

Press theprimer pumpand check forfuel sprayingout of the fuelline through asmall hole. Ifso, replacethe fuel line. YES

Remove theobstruction fromthe fuel tank or

fuel line.

NO NOCharge orreplace thebatteries.

YES

Replace theglow plug.

Try starting theengine again.

ACCESSORIES AND OPTIONAL PARTS

Graphite Radio Tray and Shock Towers

Add graphite components for lighter weightand ultra high strength.DTXC8406 Graphite Radio TrayDTXC9196 Graphite Front Shock TowerDTXC9253 Graphite Rear Shock Tower

DuraTrax Deluxe Glow Plug Wrench

This single, heavy-duty, plated steel toolhandles FIVE metric hex sizes: 7-, 8-, 10-, 12-and 17mm—and includes a special 10mmsocket for pilot shafts! Threaded holes tappedbetween the wrenches store up to four spareglow plugs. DTXR1170

DuraTrax Red Alert™ 20% Racing Fuel

To make your TORQ™ 21 engine run faster,better and longer, you need the uniqueformula of DuraTrax Red Alert. Red Alertcontains 20% nitro plus a carefully race-testedblend of castor and synthetic oils. DTXP0600

DuraTrax Nitro Starter Set

This set includes everything you need to startracing. 5-way glow plug wrench, 1 qt. of RedAlert fuel, Hobbico® glow starter w/charger,fuel bottle and glow plug. DTXP0200

DuraTrax Crankshaft Locking Tool

Remove your engine’s clutch safely with thiseasy to use, anodized metal tool. Works withall .10 to .21 car and buggy engines.DTXR1100

DuraTrax XL Field Bag

Keep your gear loaded and race ready withthe XL field bag. Heavy duty black nylon bagwith red trim and white logo. DTXP2000

3.25mm T-6 Aluminum Chassis

30% thicker than the stock chassis, and madefrom stronger, hard-anodized 7075 T6 aluminumfor even greater flex-resistance than the original.DTXC7026

Stabilizer Bar Kits

Will improve handling by limiting body roll intight turns.

DTXC9415 Stabilizer Bar Kit 1.8mmDTXC9416 Stabilizer Bar Kit 2mm

DuraTrax Kwik-Pit™ 500cc Fuel Bottle

Fast, clean pit stops are as close as the Kwik-Pit Fuel Bottle. The long, angled neck reacheseasily into your tank to prevent fuel spills, theclear plastic body keeps the fuel level in plainsight and moving fuel from the bottle to yourtank takes just a gentle squeeze. DTXP0150