Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/126069
:- I:J .c o ... u o berm er Rubio Flores, Arnie Beamo n and Jim Pomeroy (top) are the folks directly responsible for the development of next year's MXer which, while not as exotic as Bimbo's, should be By Jim Gianatsis "S u re, anythi ng you wa nt to kn ow about the bi ke j ust ask me." Bul taco's ace GP wrench seemed more th an an xio us to fill Cycle News in on Jim Pomero y's mount for th e Trans-Al\IA Series. "Wh at you're look ing a t is basically th e new 1977 produ cti on bik e," co ntinued Arn ie Beaman . "With the exception of the 3 70cc engi ne it 's the same as the bik es we ran all season in th e 2 5 0cc Gr and Prix. T h e Trans-AMA Series will give us a chance t o test and so rt o u t the b ig eng ine. an d pe rhaps by as ear ly as J anuary th e new m o tocro ssers will be available f rom dealers." Bimbo's Bultaco is definitely a neat rig, good enough to mo ve Am erica's only 250cc GP rider up to fourth place in the World Championsh ip standi ng s this year. We th ou gh t it would be in te res ti ng t o fill you in on it an d wh at Arne knew of what the new prod uction bikes would be like. The most no table lea ture o n Jim's 37 0 pr e-pr odu ct i on b i ke is the suspensio n travel, so me 11 inch es at the rear provided by th e tri ck Koni resev oir GP gas shocks, and 10 i nches up fr ont with Mar zoc chi magnesium leading axle fo r ks. The forks were bu il t specially for Pomcroy and hav e t itanium inner p arts wh ich made thcm on e pound Iighter th an s t oc k Mar zo cchi fo r ks. The :'I ~rzo cch i units arc used bec au se they arc a full 6 pounds ligh tcr than the production Bctor lead in g a xle forks Bulta co p resentl y uses , Fo r 1977. though . B eto r w ill h av e a new magnesium fork fo r th e production bikes that will be as light as the l\Iarzocchi forks and offer 10 inches of travel. The expensive Koni GP shocks obviously won't be o n an y producti on bike, but Betor is probably hard a t work righ t now on a new rear shock to allow the ne cessary II in ches of , rear wheel travel. Chassis wise. the fr ame is the sam e as the present producti on motocrossers, wi th th e excep t io n th at the 1977 models will ge t an alum inum box section sw ingarm sim ilar to Bimbo's. And lik e Bimbo 's bike. Sun rims may be used on th e new 1977 model Bultacos. The 370cc engine in th e T ran s-AMA racer is stock be tween the cases, bu i the top end has be en extensively reworked as far as porting and the addition of a reed value. Just from watching Jimmy ride the bike we'd have to say it has one of the strongest and most responsive engines in th e Open class with more usable power than an yon e else. Every time Jimmy got on th e gas, even in first gear, th e power would slingshot him instantly lorward rath er than break