Cycle News - Archive Issues - 1970's

; .s 5IG t lC) r--.. Q) ....-I maximum horsepower in their displacement class. What we will look at FlO~ are the most successful pr'oduczion motorcycles running on the "horsepower" courses used by the ~erican Federation of Motorcyclists, The: success of mese "p rea uce " mach-iRes carwi.' De measured in every case by sheer Rum ers of wins, For they are not a1'I entered in every race. Rather, we measure their success in what we term the "fear factor." When these motorcycles are unloaded at the track, everyone else in their respective classes knows that winning will be difficult. These are the bikes the other guys plot against, curse at, and inevitably, follow to the finish line. r--.. I-< II) ..0 0 ..... U 0 r" • 500 Production A SNEAK PEAK AT WHAT YOU l\IAY BE . RUNNING AGAINST IN '7 6 (AMA CONGRESS WILLING ) This is the class structure th at was hamm ered o ut at a December 20 m e e t r n g in D all a s . Te x a s. Representatives o f most of th e major road race clubs in the U.S ., particip ated. wi th A MA a ma te ur r o a d r a c e c o o r d i na to r St eve Luty acting as moderator. Si nee this is to be an am at eur program . emph asis has been placed o n givin g as m an y p eople as possible a chance to race and providin g cl ose , c omp etitive racin g fo r people w ith wallets size EEE Fat to AA AA Thin. Machines will fall in to three basic ca tego ries: Showroom St ock (which me an s w ha t it s a y s), M o di fi ed Production (Cafe) , and Grand Prix . Engin e size break do wn is as foll ows: GP AND MODIFI ED PROD. Lightw eight 0 - 200cc 2-stroke sin gles & twins 0 - 250cc 4-st ro ke singles & twins Med ium we ight 20 l -25 0cc 2-stroke twins & mul tis 20 l -400cc 2-stroke singles up to 400cc 4-stro ke mul tis 25l - 500cc 4-s troke single s & t wins Heavywe ight 25 l -7 50c c 2-stroke multis 4 0 l - 750cc 2-stroke single 40l - l 300cc 4-stroke multis 50 l - l3 00cc 4-s t ro ke sin gles & twins SHOWROOM STOCK Class I 0 - 200cc 2-s tro ke singles & twins 0 - 250cc 4 -stroke sin gles & twins Class II 20 l -25 0cc 2-str o ke, all 25l - 500cc 4-stroke singles 251 50cc 4-s tr o ke t win s & m ultis Class III 25 l - 58 0cc 2-stro kes, all 50 l -650cc 4-stroke sin gles 4 5l -6 50cc 4-stroke twi ns 45l - 550cc 4-stroke multis Class IV 58 l -7 50cc 2-stro kes, all 6 5l -7 50 cc 4-s tr oke sin gles & twins 55 l - 75 0cc 4-stroke multis Class V 75l -l 300cc all types NOTE : Th is proposal is still su bjec t to final ap proval by th e A.\ IA Jerry Elkin dominates AFM 500cc Production Facing. His Vanguard Engineering Honda gives Scott Oough "(on his 500-) fits. Yet Elkin says. "I don't knew why it's so fast - evervthing just came together." V anguard made the pistons and a special one-off cam, but no frame or suspension changes. A Goodyear slick holds up the rear, a Dunlop KR 76 the front. "It's the most reliable bike here," said Elkin before the September 21 Ontario race. "It's got 11 races on it now, and I've done no motor work," Then he proceeded to drop a valve while in first place. From San Raphael, Elkin will be the next AFl\f500 Production Champion. and in the top five overall as well. 750 Production "There is no question in my mind that this is the best bike in production racing," says Cook Neilson of his Ducati Super Sport Desmo 750. The Duck went through the traps at Daytona at 138.25 mph at 8,8 00 RPM. That was the same trap speed as David Aldana's Open class winning Kawasaki, and Cook now runs the bike up to 9,500 RPM. "The only place it gives anything away to the Dale Alexander Z-ls is in lower gear acceleration." Heavy-wall frame tubing weighs 60 pounds, but the frame does not flex. That allows use of the latest in slick technology. Cook used ultra-sticky slicks to easily beat both Reg Pridmore (BMW 900) and BOob Endicott (Kaw 900) at Riverside recen tly, and he thinks so much of the tires that he says he will give up racing if they are outlawed. Although the Duck has tremendous ground clearance. Cook has ground awa)l the kickstarter shaft. "It is very easy to ride. You never have to deal with the bike," says Cook. "You have to deal with the racetrack and the competition. but you never have to deal with the bike, because it never does anything scary. ,. Shocks 1.4" longer than stock raise the rear end to allow quicker turning. Except for a Branch FIowmetrics porting and polishing of the cylinder head. Cook says the motor is stoc k. He says his bike's exhaust system is "relocated for ground clearance." but only Jerry Branch knows for sure. Open Production Picking a .single Open bike for the "most feared" category is very d i f f icu l t , No one bike has dominated me class in AFM racing this year. According to Cook Neilson, the Dale-Star-r Kawasaki 900 piloted by Yvon DuHamel is the most feared. but that is not a function of pure machinery - Yvon adds something to the package. Cook himself owns a feared bike, in the form of his 750 - Open riders fear being beaten by a smaller machine. Steve McLaughlin is convinced that his Action Fours Kawasaki 900 (formerly ridden by Bob Endicott) is the bike to beat. Pops Yoshimura has built a lot of horsepower, b ut not much handling, into a Kawasaki ridden by Wes Cooley. Jr.. Reg Pridmore's BMW is no slouch, either. There really hasn't been a showdown to determine which bike is the bike. 29

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