Cycle News - Archive Issues - 1990's

The Honda ReJO lacks acceleration, but even so, American Tripp Noble s has been turn ing in decen t resu lts. 30 ru n co nc urrently at a ll the Europea n Superbike ro unds to keep in touch with the s uperbike scene - just as Honda's European four -st rok e tuning guru , Belgian Jea n D 'Hollander is doing! before their big comeback in 1994. The fact that they chose not to do so is probably more connected with keeping a foot in the corridors of superbike racing power than any technical reason, but for whateve r objective Rumi is runni ng American rookie Trip p Nobles on the ultimat e developme n t of the RC30, esse ntia lly unchanged fro m las t season, an d thanks to the Geo rgia n' s gritty rid ing, ge tting so me decent resul ts in doing so. The bike is completely diffe rent from the Camel Hondas running in AMA Superbike racing, w hose m uch more liberal ru les have allowed Honda to ru n bikes tha t are mo re RVF th an RC, and still delivers 147 bhp at the cra n k, at 14,300 rpm, from th e 70 x 48 .6 mm en gine, which is fitted w ith the tw in pipe exha ust system in troduced last seaso n to improve midrange performa nce in an effo rt to counter thesix-year-old RC30' s biggest handicap ag ains t more recent compe tition - its lack of acceleration. Nob les sho we d at Hockenheim that the Honda still has reasonabl e stra igh t lin e speed comp are d to a ll but the works competition, tho ugh a t 156 mph on th e BYRD speed g u n, h e h a d th e same top speed as Moineau 's Suz uki but a hug e ga p to Ga rriga ' s Ducati (166 mph) , Pirov ano's Yamaha (165 mph) and Sli ght's Kawasaki (164 mph), the three fastest bikes in a sam ple tak en just before the braking point for the entry to the stadium, so not the fastest part of the tra ck, perhaps. Fogarty's 888 (not 927cc) Ducati was timed at 178 mph en route to victory in the North West 200 in Ireland a w eek later, and a German magazine had him at 179 mph at Hockenheim, ahead of Garriga (177), And y Hofmann ' s and Sc ott Ru s s ell' s Kawa s a k is (176), Pirovano and Slight (176) and Nobles (168). Shows h ow much development has tak en place since the advent of the RC30... Rumi crew chief Merlyn Plumlee ha s been experime nting with airflow to the 38mm Keihin CV carbs that are the main rea son the Honda' s no longer on th e pace, with two sm all diameter hoses (as big as there's room for) leading from the nose of the fairing to a fully sealed airbox, with ai rflow around the rad iators in the Superbike class by' fittin g the bike with the ir quirk y 38 m m M ik u ni Slings ho t carbs (with no homologated flatslides), a nd d ecli ned to g et involved on a n official basi s with world-cla ss supe rbike racing. And in sp ite of displayin g a fullrace v ersio n alongside the road ster W-mod el at th e Europea n lau nch thereby creating expe ctation s th at have s o far been unf u lfilled, Suzuki ha s relea sed no ra ce kit fo r th e bike , n or an ythi ng a p p ro a chi ng th e RR version of the old oilpumper GSXR. To show what migh t b e possible, Suzuki ' s lon gtime Fr ench e n d u ra nce s p e ci a lis t Dominiqu e Meliand entered Herve Moineau in a co u ple of World Superbike races last year, so n - b u t a t present, we are not corn- " petitive, ye t we have a bike tha t is cer tai nly capable of challenging for a rostru m p lace with some committed input from all sides." The 70 x 48.7 mm watercoo led eng ine thus contains a mixture of bo th Japanese a n d European tuning p arts: the 13:1 forge d pis tons are Euro-sourced , for ex a m p le , w hereas the s pecia l rod s, ca ms ha fts and ig n ition come from the factory. Oversized valves ar e fitted, with of course the stock Slingshot carbs and a carbon fiber airbox behind the cylin de rs made by Su zuki Fra nce . The cy linde r head has been flowed a n d rew orked , with spec ial valve sp rings, and a factory exha us t. A wo rks close-ratio gearbox is ma te d to a dry cl u tc h o ff one of Melland 's s ucces sful end ura nce racers, complete with filler plug for toppi ng up the oil level in a 24-hour race. Meliand says the engine delivers 145 bhp at the gearbox, a t 13,300 rpm perhaps reflecting the fact that the Suzuki engine has a longer stroke than ei ther the Kawasaki or YZF Yamaha. The distin ctive Suzuki chas sis on the ' beautifully-p rep ared 365-poun d b ike Herve Moineau races the only Suzuki GSXR750in the field and often find s himself well off the pace. eli mi na te d by sh ro ud ing . The result has been cleaner carburation , bu t also a dramatic decrease in engine tem perature oil temperature is runn in g 20 d egrees cooler th a n b e fore, says Plu m lee, m eaning the te am h a s d is p ens e d wi th an oil cooler and is running sm a ller wa ter radiators than last yea r a re markable fact, given that o ve rhea ting was a lways a p roblem w it h th e V-fo ur Hond a e ngine throu ghout its life cycle. Another ex peri ment th a t ma y y ie ld u s e fu l benefits when the RC45 comes along is the pair of sw ing arms the Rum i team hav e been tryin g out this season, the latest one a factory spec ial w ith hea vy bra cing over th e t op of the upp er ch ai n run, to cre a te a tunnel giving ex tra stiffness. With the and was rewarded with two fron t-row has been braced up where feasible, and fitt ed w it h a works swingarm, 15mm rum ored 160 bhp-plu s th e RC45 is grid positions by way o f enco u ragelo nger than s tock, to give a sligh tly reputed to be deliver ing, this will sure ly ment. Thi s season, Suz uki actua lly won b e needed , but oth erw is e th e Rum i ra ngy 1450mm wheelbase. the firs t round of the Japanese F-l series, RC30 is unchanged from last season, fitIn a major d epartu re fro m estabbut of course that class p ermits raci ng ted w ith Showa suspension and scali ng carbs as well as trick chassis. Still, cou. li s h e d p ra c tice , Melia n d has fi tted pled with the news th at Meliand was Ohlins su sp ension (the front forks the right on the 363-pound weight limi t. Its s ma ller 4 2m m v ers ion ) rath er th an place is already reserved in th e Rumi planning to run Moineau in a full seaso n of World Su perbike racin g, it seemed private museum, bu t meantim e Oscar Su zuki's traditional Kayaba su ppliers' that Suzuki were finall y go ing to make has more pressing concerns - like interproduct s, en tire ly b ecause of th e onviewing the line of rid er s, some of them their mark on the four-stroke cla ss, in t rac k p add o ck service th e Sw ed ish the same way they're fina lly reaping the with existing factory teams, s ud denly co m pany provide a t each ro und. The .interested in presenting their resumes to reward s of yea rs of endeavor in 500cc te chn ici an in c ha rge o f this is GP ra cing th is s e aso n with Kev in An dersson, for many y ea rs Suzuk i's him with an eye on next season and the Schw antz. return of the Big H, big time. The sup erleading Europea n fo u r -s tro ke rid er bike paddock is waiting, but Rumi and until he sw itched to Yamaha on which . Sadly, it hasn't happen ed. Moineau Jean D'Hollander are hoping, too . on the o n ly Suzuki in th e fi eld ha s he brought his racin g career to an end, been righ t off the p a ce, and u sually an d he ha s no doubts why the Suzuki Suz uki : Are you in or out? b att lin g to b e at newcomer Tripp isn't on the pace. The Suzuki factory' s lack of commitN obl es on the eld erly, outpaced RC30 "It's th e fault of the carb s, " sa ys Honda to av oid bringing up the rear in ment to four-stroke racing at the highest Anders son. "They don't flow en ou gh air the roll-call of marques. Dominique level is one of the superbike class' grea t and ar e th e wrong d esi gn for racin g m ysteries . After launching th e wa te rMeliand can't hide h is fru str ation: th e Sli ngsh o t was develop ed to give cooled GSXR750W at the end of 1991 "This effort is 100% French, or ganized, smooth response for the street, not make pow er for the track. The engine has a lot with an on -the-record a d m ission th at funded and developed by our team," they were switching from their tradehe says. "We've had some help from of . potential and M eliand has a go od ma rk oil-cooled engine because " th e the fact ory In sourcing cer ta in parts; operation which can d o w ell in supe ra m ou n t of heat generated in tod ay's' but ba sically we're on our own, and 1bike racing, but perhaps the factory's must say I had hoped for greater supresources ar e too stre tched trying to win motorcycle racing with strin gs of highp itched battles is simply en ormo us," the 500cc titl e, so the y haven't got an y port from Japan. Wh ether we manage to see out the season will depend facilities to sp a r e to make a seriou s hence the need for watercoolin g. entirely on what backing they decide Su zuk i then effecti vely prevented effort in superbike. It's a pity." Amen to that. (N to give us in the second half of the seaanyone from racing the bik e successfully

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