Cycle News - Archive Issues - 1980's

(Above) Wayne Rainey 's Maclean Rac ing RS250R , with RS500 front end and 17-inch whee l; (below) RS250RWwith works forks have magnesium sliders and 16-inch wheel. it at LeMans wi th Sami n hopin g to be fit eno ug h to j oin Did ier d e Radigues o n th e sta nda rd Elf-spon sored Honda triples. De Radi gues is th e o n ly o ne of th e Elf team to rid e the fa ctory spec ia l NS500 inst ead of the production RS500 and after half a sea so n o f experimentation with special angled fork yo kes a nd len ghen ed sw ingarm s de Radig ues went back to co m p letelystandard ma chines for the Dutch 'TT nd says h e intends to stick with th em for th e rest of th e year. aldwin's NS /RS500 Wh en is a wo rks bike not a works ike? When it is ridden by Mike aldwin, seems to be th e ans wer . The rnerica n Champion has now received triple ATAC sys tem to rep lace th e TAC chambers on the upper two ylinde rs wh ich is standard eq u ipen t on th e '85 production RS500 ondas. He already had some lighteigh t cra n ks a nd pistons with light udgeon pins an d no w th at he ha s he three ATAC bo xes h e is a s close as n y privat eer is lik el y to ge t to riding factory bik e. Along with th e three \ T AC boxes went th e cylinde rs, albeit econd hand , with sligh tly d ifferent ortin g, th e n ew pipes and a bigger adiator to keep th e lot coo l. T he wet nd disma l Du tch T'T wa s not the lace to find a u t if there was a power ncrease but th e bike was certa in ly lying wh en he got to Spa wh ere it limbed th e hill aw a y from th e sta rt nd fini sh a rea as fa st as an y ot he r ree. pencer's 250 unveiled Honda took th e fairing off Freddie pencer's 250 twin for th e first time at Spa . In do in g so th ey reveal ed little more th an the photos a lready seen in th ese pa ges. sna p ped when th e bottom half of th e fairing was removed in th e pit lane. The twin, which is half of th e Vfour with th e sa me 54 x 54m m bore and stro ke has th e water pump a nd ATAC drive o n the right hand sid e o f th e engine. Both of th em a nd th e cl u tch a re driven off a gear onthe en d of th e cra n k. On th e left hand end of th e cran k is the ignition rotor. The sin gl e -ca st ing, twin-choke ca r bs breathe into th e crankcases direct through reed valves situated o n the top of th e gearbox. (Below) RS250RW's twin-choke carb feeds cases through reed valve, freeing up rear of cylinder for more ports area; RS250R (above ) has cylinder reed valves, two carbs. (Below) Martin Wimmer's new works TZ250 features a YZR500-style aluminum frame and is pre-production version of the bikes Yamaha will sell in 1986. NewYamahas Both Martin Wimmer and Carlos Lavado received new works TZ250 Yamahas at Assen. The main feature was th e new twin-spar a lu m in u m frame that looks ver y much like a small veri son of the YZR500 and used th e sa me su spension system with a vertical un it in front of the rear wh eel and linkages co n necting its lower end to th e swingarm. The engines were different as well , featuring new cylinde rs made especia lly for th e 250 in stead o f those p reviousl y used by Wimmer a nd Lavad o which were from th e 500 development and did not fit th e cra n kcas es neatl y. T he new engines were much more tractable and Wimmer mi ght have used hi s in th e race but it seized in th e untimed warm-up sessio n o n Saturday m orning . H e could n ot put o ne of th e other en gines in th e al uminurn frame because th e engine mounts have been changed. These bik es are pre-producti on ver- sio ns o f next year's machines th at will be for sa le to o ne a nd a ll an d seem to he far better than th is yea r's reed valv e machines that hav e not p ro ved co mpetitive in G rands Prix, lawson no to rumors T he ru mors co ncer ni ng vari ous fact or y riders cha nging team s for next season have sta rte d ea rly this year. Severa l Europea n pa pers ha ve ca rr ied sto ries a bo u t Eddi e Law son leav ing Yamaha to rid e for Suzu ki. In o ne pa pe r it was to join Sit o Pons in the HB team a nd in a not her to be with Rob McEln ea o n t he green -andwhite Skoa l Bandit machines. Hi s associa tio n with Pons appea red in a sro rv th at h ad hi s sig nat ure o n th e bot 10m but even rh ar wa s eas ily exp lai ned . " T here is no tru th in a ny story a bo ut more rid in g for Suzu ki, I m ight ride o ne, I m ight ride a ny th ing but I ha n ' not tal ked to a n vo ne a bo u t . it yet. I don 't mind talk in g . T a lk cos ts n othing bu t I haven 't spoken to a n yo ne. I signed a piece of paper that these Spanish guys put in front of me 19

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