A DIFFEREIUTTRIUNilPHYou Soy the Bonneville Weighs Too Much? Well . . .

by Chuck Johnston

I f u r ider spent years campalgnrng a

I Triumph TT bike on southern Cali for-I nia tracks, i ts easy to imagine his view

of a street Triumph might be quite dif-ferent from the current offering from Mer-i den . I n add i t i on , a p r i va te i nd i v i dua lwould be exempt from most of the govern-mental regulat ions that so often hamper afactory effort. John Calicchio is a youngman from Costa Mesa, California who fillsboth of the roles described above. Al-though he owns JRC Engineering, a com-pany that designs and bui lds replacementand competit ion/perfbrmance parts forTriumph Twins. he has years of dirt trackexperience behind him. And John's idea ofa street bike, as you can see from thephotos, is clearly influenced by his racingexpenence.

It certainly couldn't be r idden in the rainand i t 's a long way from the ideal touringbike-even freeway commuting looks un-comfortable on this spartan rnachine. I t is,

as John describes i t . a fun bike to r ide onSunday mornings and occasional ly r ide to

/ lunch i f the skies are clear. The fact that i t 'sa rol l ing test bed almost seems incidentalto John and actual ly the bike shown in ourphotos is only one of several identical bikesthat John has bui l t and kept around for thetesting of his products. A few have beenbuil t and sold to special customers butJohn seems so fond of his yel low beautiesthat i t 's hard for him to let them out of hissight for more than a few hours.

Knowing we would treat the bike as oneof our own. John agreed to loan us one totest alongside our 1978 Bonnevi l le. Wedidn't seriously want to direct ly comparethe '78 factory bike with a custom-buil t ,semi-legal private effort but as you mightguess, i t was hard not to get off the

'78

Triumph and on John's special Triumphwithout comparing the bikes. More on thisshortly.

ln the case of our test bike. John started

with a 1965 l iame and cut off al l unneces-sary lugs and brackets before it was sentout to be nickel-plated. John used DunlopK-70s on al loy Sl inger r ims that were lacedup to Barnes competit ion hubs. Hurst discbrakes are fitted front and rear. Ceriani.flattrack-type forks are used in combina-t i on w i t h G i r l i ng rea r un i t s . John ex -plained that while they put Koni or Bogeon the race bikes, the shorter Girling rearshock is used because i t cuts the seat heightdown to a low 29 in. The fork legs aredropped in the top clamp to keep the bikelevel.

The fiberglass tank holds only 2.2 gal.but John admits you're ready for a rest stopafter the 100 miles or so that this al lows.JRC Engineering makes the seat As well asthe a lumrnum o i l t ank unde rnea th . A'Ba tes

accesso ry head l i gh t and t a i l l i gh tmeet the Cali fornia requirement, with thedintmer switch located on the headlight

APRIL 1978/57

she l l .

I he brke we borrowed had a nearlystock 650cc engine that had been balancedand used one of John's Mikuni ki ts. On thes ing le ca rbu re to r k i t s , John supp l i es a34mm M ikun i . The re a re two 32mmMikunis for the Bonnevi l le models. TTpipes and a Mity Max sol id-state ignit ionare the only other modif icat ions to thepowerplant. John uses Kenny Harman's# l5 cams in the more ser ious engines andhead work is usually specif ied. Our testbike had a stock cam and stock heads.

John 's own a i r c leaners . bu i l t by K&N.f inish off the carburetion with Barnettcables and controls used throushout thebike. Barnett also supplies the cJmpetit ionclutch instal led in al l of John's bikes.

Testing the two Triumphs together wasinteresting because our test crew was ableto commute between what amounted to apair of dif ferent Twins. The seating posi-t ion on John's bike and the K&N f lattrackbars left no doubt in our minds that thismachine was sired by a dirt tracker and i fthere are any doubts. the exhaust notequickly dispels them. It would have to bedescribed as barely legal.

The feel of the clutch lever is st i f f andabout what you would expect on a com-peti t ion machine. Once warmed up i t wastrouble free for the remainder of the day:something we couldn't say about the '78

Bonnevi l le. Tech Ed. Len Vucci was sur'-prised at the effort necessary to stop thebike with the lront brake but then dirttrackers seldom have front brakes that willlock when applied hard. Don't misunder-stand; the bike stopped well- i t just took abit more effort than we are used to on streetbikes.

Our test ing on the drag str ip proved lessthan satisfying. Seems one of John's wellmeaning employees had used Armor-Al lon the seat . Whi le Armor-Al l is cer ta in lypopular for many uses. i t should not beused on seats-especial ly when you wil l bewearing leathers. On the f irst accelerat iontest. Vuici let out the clutch and promptlyended up with his crotch over the tai l l ightand the bike in a 200-ft . wheelie. As Lendescribed i t . " l t was a bit dif f icult to set

forward and rol l of l the thrott le." Justanother thri l l in the l i fe of a test r ider.

Since I was wearing Levi 's, I was electedto give i t a try but fared l i t t le better. Ourbest t imes for the quar ter mi le were 13.7sec. and 93.84 mph. S l ieht lv bet ter . thanthe new Bonnevi i le bui then we had al00cc smaller engine and a very sl ipperyseat.

Several of us took turns r idins John'sbike on the road racing course. Tf,e bike'sl ight weight became apparent. as i t couldbe thrown from side to side almost l ike amotocrosser. Even with the old-style K-70s, the bike held an easy l ine in hardcornering and only the f lattrack bars keptus from feeling like road racers. We allspeculated on the weight of the bike buteven John admitted he had never weighedit. Late that afternoon we rol led i t on theCW scale and much to evervone's surorisethe bike ' .r 'eighed only 3 12-lb. Len dldn'tquite bel ieve i t so we checked the cal ibra-t ion on the scale and weighed i t again foranother 312lb . John jus t smi led and sa id ." l t must be those l ightweight wheels andhubs." Anyone who c'ver picked up a stockm idd le -S i x t i es T r i umph f r on t -whee l as -sembly would agree. I 'm sure the frontwheel on my old Trophy weighed the sameas my daughter's Honda Z-50. An interest-ing side note was the front/rear weight biaswas exactly the same as the Husqvarna 250CR that we tested in our February '78

issue. John would be the f irst to admit thebike would be out of place on a motocrosscourse but then the Husky might look a bitodd at Ascot park.

As mentioned earl ier. we don't meanthis as a definit ive comparison between the1978 Bonnev i l le and John 's spec ia l TTlStreet bike but rather as a look at twototal ly dif ferent concepts in design andstyl ing. John's bikes would never appeal toanyone except an enthusiast who has comeunder the spel l of dirt track racing-eitheras a competitor or a spectator. But then,even r iders of the 1978 Bonnevi l le mightadmit a certain fondness for the sounds ofa racing Triumph on a dirt track and thesmel l o f castor o i l mixed wi th damo ear th .

Nearly stock 650cc engine is, er, at /eastadequate for the 312-lb. roadster and hasreceived /ots of elbow,grease and polish.

s8/CYCLE WORLD

Shorf Girling shock lowers stock frame, seatand center of gravity.

One disc brake is plenty. lt does take ahealthy squeeze, though.

SPECIFICATIONSList price .$2500Suspens ion , f ron t . . . . . . . .Cer ian i f la t t ra :kSuspens ion , rear . . . . .G i r l ingT i re , f ron t . . . . . . . . : . . . . .350-1 9 Dun lop K-70Tire, rear . . . . .400- '18 Dunlop K-70Eng ine . .1965 TR-6 Tr iumphBore x stroke. . .71 x 82mmP i s t o n d i s p l a c e m e n t . . . . . . . . . . . 6 4 9 c cCompress ion ra t io . . . . . . . . . .9 :1Cla imed power . . . . . . . .43 bhpCla imed to rque . . . . . . .naCarbure t ion . . . . . (1 ) 34mm JRC Mikun ilgn i t ion . . . . . . . . . so | id s ta te Mi ty MaxLubrication system . dry sumpOi l capac i ty ( t ransmiss ion) . . . . . . . . . .500ccFuef capaci ty . . . . . . . .2.2 gal .Recommended fue l . . . . . . .p remium.Starting system .. folding kickA i r f i l t ra t ion . . . . . . . . . . . JRC by K&N

POWER TRANSMISSIONClu tch . . . . . . . . . .mu| t i -p la te wet

w/Barnett d iscsPrimary dr ive duplex chainFinal drive . # 530 Reynolds ChainGear Ratios

DIMENSIONSWheelbase. . . . . . .55 in .Seat he igh t . . . . . . .29 in .Seat width .9 in.Hand lebar w id th . . . . . . . .36 in .Footpeg he igh t . . . . . . 11 .5 in .Ground clearance . . . .4.75 in.Front fork rake angle . . . . . .27 deg.Tra i l . . . . . . r raCurb weight

( w / h a l f - t a n k f u e l ) . . .Weight bias, front /rear,

percent .45.5/ 54.5

FOR

e set out to do a shor t ar t ic le ont h e s p e c i a l s t r e e t / T T T r i u m p h

w h i c h J o h n C a l i c c h i o p u t s t o -g e t h e r i n i i m i t e d n u m b e r s a n d w e n osooner f inished the piece when John let ushave a look at a newer-than-new competi-t ion-on ly machine that w i l l be raced on theNat iona l TT c i rcu i t in 1978. Bes ides be ingthe state-of-the-art in TT machinery. themachine impressed us wi th John 's a lmostuncanny at tent ion to deta i l and esthet ics .As evidenced by the street TT bike detai ledelsewhere in this issue. his bikes look asgood as they run. The bikes drew crowdswherever we rode them. Questions l ike,

" ls

i t a racing bike? I thought f lattrack bikesd idn ' t use brakes. What k ind of pa in t isthat? Do they st i l l race Triumphs?"

The last question was heard more thanonce and rve found ourselves recal l ing thesuccesses of the Brit ish TWins in last year'sfT season. No one wants to be pinneddown on why an engine des igned in 1938can st i l l be competit ive but whatever thereasons. the 650cc engines rebored to 750ccare enjoying renewed interest and activi ty.

John started with a Trackmaster TTlrame. identical to Trackmaster's half ' -milemodel. According to John, dif ferent foot-pegs are supplied i f you wil l use the framefor half-mile because the current trend isto put both the gear change leyer and thebrake pedal on the r ight side. We weigheda new Tiackmaster lrame and noted that at3 l lb . i t was on ly 12 lb . l ighter than thestock Ti iumph frame-we al l expected agreat dif ference. Another surprising com-

pa r i son was head ang les . The f ac to r yf iame measured at 27 deg. and the Track-master at 26 deg. Again we expected agreater dif ference but John feels the fac-tory lrames \,\'ere not far from right for dirtt racks. One other var ia t ion is that theTrackmaster frame carr ies the oi l in thebackbone of the f rame, e l iminat ing theneed l i r r an ext ra a luminum tank underthe seat .

As on h is s t reet /TT ' b ikes. John usesSl inger r inrs f ront and rear but ins tead ofthe l8 in . r , rhee l on the s t reet b ike. thecompet i t ion TT b ike uses l9 in . wheels onboth ends. The wheels are laced to Barnescompet i t ion hubs which at tach to Hurs t /Airheart discs-double in the f iont and asingle at the rear.

Afler looking at Pirel l is and Dunlops formore years than we care to remember.we're seeing the new Goodyear DT-2 t iresgain populari ty on the dirt tracks. Johnuses a 350-19 at the f ront and a 400-19 atthe rear. As you can see in the photos, theprofi le on the rear t ire offers a much widercontact area and according to John, muchless wheel spin is evident.

The Ceriani f lattrack fork is used upfront but incorporates slightly differentspring rates and damping than the modelwhich John uses in his street specials.Mulhol land-lnterpart rear shocks are usedand early tests indicate that running theunits in the rear-most posit ion on theswing arm offers the best combination ofhandling and wheel travel.

Flanders TT handlebars are used. Most

of us were surprised at the narrow feel withon ly a 32 in . w id th but John te l ls us therather crowded cornering condit ions f i i r , 'orthe narrow bars. Both the 2.2 gal. gas tankand the seat/rear fender combination arefiberglass. Between the narrow tank, seat,and handlebars. the feel of the bike isa lmost that o f a t r ia ls machine.

The engine left the factory as a 1966'f R-6 but has been bored to 76mm from thestock 7 lmm, which increases the d isp lace-ment to 744cc. Hepoli te pistons are usedfor a conservative compression rat io of9 .5 :1 . John exp la ined that p is tons wi thhigh domes tend to detract from overal lpower output because of a ci isruption ofthe f lame front as i t travels ercross thecombust . ion chamber

continued on page 167

SPECIFICATIONSList priceSuspension, front

.$4800flattrack

Suspension, rear . BogeTire, f ront . . . .350-19 Goodyear DT2

.400-19 Goodyear DT2.1966 TR-6 Tr iumph

. . . 7 6 x 8 2 m mPiston displacement. . . . . . . .744ccCompression rat io . . . . . .9.5:1Cla imed power . . . . . . .63 bhpCla imed to rque . . . . . . .naCarburet ion . . . . . . (2) Del lor to 34mm

PumperslgnitionLubrication system. . dry sump-oi l

in frameOi l capac i ty ( t ransmiss ion) . . . . . . . . . .500ccFue l capac i ty . . . . . . . .Recommended fuelStart ing system . . . . .A i r f i l t ra t ion . . . . . . . .

POWER TRANSMISSION..mult i -p late wetw/Barnett d iscs. . . . . d u p l e x c h a i nReynolds chain

PROFESSIOWOIULY

A TT Triumph for Show ond Go by Chuck Johnston

Primary driveF ina l d r ive . . . . .Gear Ratios

4 th .3rd2nd1st

DIMENSIONSWheelbase. . . .Seat height ..Seat widthHandlebar widthFootpeg height . . . . . .Ground clearance . . .Front fork rake angle

(w/hal f - tank fuel) . . . . . .Weight bias, front /rear,

percent

. . . 1 . 11 . 1 9 : 11 . 6 9 : 12.44:1

. 5 5 i n .

. 3 0 1 . 0

APRrL 1978 /59

continued from page 59

The connecting rods are bui l t by John'sown JRC Engineering and are forged alu-minum. John bolts these to the heaviestflywheels he can find to further reducewheelspin. Then the entire assembly isbalanced and bolted into Triumph casesthat have been modified for improved oilcirculation.

The heads have been modified by con-ventional porting and polishing and theinstal lat ion of 42.5mm valves. The exhaustvalves are stock diameter and both valveshave S&W springs. Kenny Harman's K&H# l5 cams are used for a total duration of288 deg. on both the intake and exhaust.The cams are, according to John, identicalto the Jomo # 15 cams used with suchsuccess on the factory entries of the lateFifties and early Sixties.

The carburetion consists of two 34mmDellorto pumper units that provide animpressive throttle response. As much asJohn hates to abandon his beloved Miku-

Trackmaster swing arm has choice of shockmounts, but the bike seems to work best withthe Mulholland shocks set to the rear. Notedetailwork on the hub, brake and swing arm.

Ceriani competition forks carry Slinger rim,Barnes hub and a pair of Hurst-Airheart discbrakes.

Ital ian carburetors. The spark is providedby a Gilmer belt-driven ARD magneto.Unlike the magneto used for years on theT r i umph rac ing b i kes , t he new mode lprovides a rotor and cap that allows theplugs to fire only at TDC compressionrather than f i r ing tw ice for each fourstrokes-once at TDC compression andonce during the exhaust stroke.

It 's dimcult not to compare this bikewith Jay Springsteen's XR750 we looked ata few months back. The bikes are bothbuil t to compete professional ly on dirttracks but the dif ference in appearance isincredible. While Jay's Harley appearedall business and almost brutal, John's Tri-umph looks more del icate and has a cer-tain ref inement. Of course John's bike wil lsoon bear some of the scars seen on Jay'sHarley. We can't help but feel i t 's a shameto push such a pleasing piece of machineryout on the track. Couldn't John just hang i ton the wall in his off ice and keep i t in, i tspresent condit ion? o

nis, he admits a power increase with the

Engine began life as a 1966 TR-6. lt's bored to 744cc and has big valves,flywheels, carbs and a magneto. lt's a work of art and it works.