Cycle News - Archive Issues - 1980's

Yamaha 's 1985 YZR500 has been refi ned and im proved to reduce engine vibration, broaden the powerband, im prove cooling and reduce weight . Specific changes to the YZR500 include new carburetion , a stronge r frame, new forks and swingarm and changes in weight distribution . simi la r to th at use d on th e th ree, wi th th e gas tan k in the usual position. T hat ma kes sens in that the triple has been so success fu l a nd some o f th e information acq u ired from th e NS500 wa s used to devel op th e N SR . Another area o f cha n ge with th e four is in the coo ling a nd a ir inta ke syste m. T he four ra n 50° F hotter than the threes, perhaps because th e du cting syste m for cooling an d intak e ai r was co m p lex a nd too res tr ict ive. The V-four Yamaha ha s its ca rbs facing fo rwa rd , ea sily su p p lied by coo l. fresh a ir. Th e Honda has its ca rbs behind th e cylinde rs and th ey must be fed ' ro u nd the en gine. PUll ing the p ipes back under th e eng ine would help keep th e airbox coo l. No matter wh at it does, H onda ma y run up aga ins t th e problem that th e NS500 tripl e is a very hard machi ne to improve o n. Yam aha has ba tt led for th ree years with th eir Vfours , a lways findi ng that th e H o nda three was su ch a well- balanced ma ch ine that it was hard to beat. H ond a had to ad m it la st vear th at th eir four was not as good and th e same ma y be tru e in '85, th e extra power being m or e o f a n embarrassment than an adva n tage . As Spe ncer said a fter th is wi nter's tests in Aus tra lia, " We w ill ha ve to wai t u ntil th e So u th Afr ica n G rand Prix to find OUI." T h ere seems n o reason for Ya maha to m ak e maj or changes to their machi ne , a lt hough th ere were so me ca rburerion troubles th at ca used part icu lar p roblems a t Pau l R icard a nd, of co urse, th e rea r wh eel tra cti on diffi cu lties th at cost Lawson in Yugoslavia a nd Belg iu m . The shorter swinga rm th at Kenn y Robert s firs t used at La gu na Seca improved th in g s b ut th a t a rea still ' req u ires a ttentio n in co nj u nct ion with tir e devel op ment , It seems tha t Yam aha has sw itch ed to Michelin tir es a fter usin g Dunlops for th e last fo ur years. In th eory th a t puts th em on a par with H onda a nd Suzuki who have been using the Fren ch tir es. There are lik ely to be a rguments, th o ugh , as o ne tea m seems to get better trea tm ent th an th e o ther because the same tires will never sui t all the mach ines and riders. Yamaha ma y a lso h a ve to revise th eir steer ing geometry because, a lth o ug h bo th Yamaha and H onda h ave bee n headin g in th e di recti on of 17-in ch fron t tires th e Mich elin 17s have ver y short side wa lls a nd hav e a ro llin g dia meter more li ke th e 165 which h ave been used so successfu lly bv th e Mich eli n -shod H o nda s and S;'zu kis in recent years. T h e 17-i nch Dunlop th at La wson used in 1984 was nar ro wer a nd had a la rger d iameter tha n a ny 16 . T he re will be a th ird works Yamaha run in th e So na u to Gau loises co lors who is also ca pa ble o f win ni ng ra ces." T hecyn ic mi ght suggest that Lawso n is h appy to see the fiery Fren chm an in h is ow n tea m rat h er th an have to clas h fa irin gs with h im again . T he Ca lifo rnian's reserved riding through most of '84 mad e him stay clea r of Roche's spectac u la r o u tbra king maneu vers. H e backed off to let Roche and Mamola battle it o u t between th em a t Assen but stuc k to h is gu ns a t An derstorp whe n last-lap braki ng took Roc h e off the tra ck. Roc h e's o n ly cras h was in practi ce, th ough, and very few o f th e to p 500 men fa ll to ea rt h - Spencer 's acciden ts were most sur p rising. H e ca n n ot affo rd a nother seaso n like that and Mamol a wi ll be less incli ne d to ' p la y th e d utiful tea mmat e as h e d id in '84 whe n he cruised the last lap in Aus tria to let Spen cer ta ke seco nd . Co nce ivably tha t co u ld have cos t him the cha mpions h ip at th e en d of th e da y a nd aft er fin ishing seco nd in th e cha m p ion sh ip th ree ti mes Mamo la will be taki ng every point. no ma tter who from. He joins Spencer in th e Ro th m a n 's H o nda co lors as does ex350 cha m p io n T ak azu mi Ka ta ya m a. who missed most o f '84 th an ks to an end-o f-seaso n in jury in 1983. Marn o la ge ts a n upra ted NS500 triple a lthough if th ings go the w ay- th ey Now teammates sponsored by Rothmans: Americans Randy Mamola (left) and Freddie Spencer. for 250cc World Champion Christian Sarron . T he Fren chman h as race d 500s before, in '79, '80 a nd '8 1 bu t a lthough he has a lways preferred th e bigger-capacity machi nes and was ru nner-up in th e 1977 Form u la 750 Champions hip, he never had m uc h lu ck o n a 500. H e crashed m ore often th a n wa s prudent but Sarron says th ree seaso ns' m or e experienc e h ave made all the differen ce and he obviously wants to add th e 500 class to hi s 250 crown. T hough Sarro n and Roche are bot h ridi ng Ya mahas, La wso n ca nn ot exp ect the m to follow tea m o rde rs. For the first half o f the season a t least it will be everv man for himself a nd while it mi g ht take Sa rro n a wh ile to a ttune hi mself to th e 500 - which he has a lready tested in J ap a n - Roc h e wi ll be eager to get stuck in from th e word go . H e st ill h as to wi n his first G P af ter fin ishing seco nd four times in '84 a n d I ca n n ot see hi m h o ld in g back in Sou t h Afri ca. L a w son , th o ugh. is ha ppy to see him replacin g Virginio Ferrari. " I cou ldn' t wis h for a nyone bet ter to h ave as a tea m mate. O f all th e gu ys a vailable, Roche is th e o n e 1 wou ld have chosen if the decision was m in e a lo ne. It wi ll be grea t to have someone in th e team who ca n help and sup port me a nd ,' did last year he might ta ke up a n o ffer' to ride th e fo ur as he did la st year to w in th e British GP. One change in th e Mamol a tea m is the loss o f New Zeal ander Mike Sin cla ir who goes back to Suzu ki a nd the arriva l o f ex R hodesia n Nobby Cl arke wh o spe nt a trying yea r with Cagiva a fter leavin g Yamaha wh ere h e h ad been a n importa nt p art of the Roberts' dominance. AlongsideMarnola on th e works trip les are Brita in's Ro n H aslam , Australian Wayne G ardner a n d Bel g ia n Didier de Radig ues. Like Ma m ola th ey were all to have fo und their o wn sponsorshi p money to ru n th e wo rks bik es. As th e beginnin g of the season a p proach ed, things looked bad for Gardner and H asla m wh o need ed big money to run th eir bikes. T hey were rescu ed by a sponsorsh ip deal betw een Ro thman s in Britain a nd Honda Brita in wh ich provided enoug h money for both th e GP sq ua d and a home F-I team. Mamo la wa s adop ted into the J a p an ese factory Rothm ans H onda team over a month after th e announcement of the Spen cer-Katayama squad . Finding sponsorshi p was eas iest for de Rad igues who had the Fren ch oil co m pa ny Elf eager to wr ite th e check: With th e money a lready in the 13

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