Cycle News - Archive Issues - 1990's

take a corner at least one gear higher tha n you 'd inte nded to (tha t's if you're lucky and it 's not hit a neutrall ), all of which is scarcely conducive to fast lap times. My best lap of I minute, 16.4 seconds at Snetterton (against Steve Spray's I: 13 3 at the Race of Aces) included a false neutral going into Ri ches, and I'm convinced that the gearbox defects alone are worth over a second a lap at Snetterton to Messrs. Spray and Nation , simply because of the time it takes to change gear. Of course, it's quite impossible to change up, withou t the Clutch, which must be a major han dicap in the Isle of Man o r anywhere else where you need a ll your strength to mak e the bik e go where you want it over bu m ps and can 't afford th e luxury of tak in g your fin gers off the bar to cha nge upw ards using th e clutch. In fact, a lo t of work ' on the mech anism of the now dry multiplate clutch by the team has smoothened up the actio n no end: it's the gearbox that lets the side down badly still, as a result of whi ch you try to use it as little as possibl e, using that wide powerband and flat torque curve to hold the bike in gear while you screa m th e' en gi ne to 11,000 rpm and more alo ng th e sho rt stra igh t between Rich es and Sear, o r from the Esses to the Bomb H ole. After a while, you learn the Approved T echnique of riding th is fast but flawed motor cycle, whi ch is to get your down-shifting done early for a given corne r so as to leave a cer tain margin for error, but then use the ro tary's almost total lack of engine braking to coa st into turns with the po wer off and. th e clutch The aluminum twin-spar Spondon frame, painted black for 1990, is a "serious understeerer," and presented a 'challenge to chassis consultant Ron Williams. in December '89, certain budgetary decis ion s had al ready bee n ta ke n whi ch meant we did little or no work on engi ne development over the winter," admits Barry Symmons. " We . th ought we had enough power in hand to ena ble us to keep ahead of the field in 1990, but that tu rned out to be a fa lse assumption , mai nl y because Yam ah a made a big effort to get o n terms in World Su perbi ke, which rubbed off o n their British F- I team . " We a lso changed tire rnanufactur- The exhaust system is called on to vent exhaust from the rotary engine which runs at approximately 1100 degrees Centigrade. 16 home, wh ile braking very hard and late. . The Spondo n chassis steers well off the power, so tip it in to the apex and try to maintain momentum as yo u prepare to take a big handful of throttle just as yo u hit the apex. Be ready to fight hard to pull the bike back on the line you want it to foll ow rather than th e one it wants to go in wh ich will be towards the outside of th e turn: shift your weight forward on the tank and try to keep th e front wh eel on th e ground as you look for the early drive out of the corne r without your progress being impeded by the spluttering and misfiring you 'll certai nly encount er if yo u try to feed the power in slowly and gradually. In other words, this is a bike that demands to be ridden in an all or nothing manner; and it is most definitely not an easy 'ma chine to ride a t anyth in g approaching co m peti tive speeds. Messrs. Nation, Spray and Dunlop: Take a bow ! Not easy, but fast, even if this season the Yamahas especiall y seem to have had an undoubted edge over the rotary racers even i n the power stakes wh ere Norton was previously top of the class . "When I took over running the team chassis , a nd th at was defin itel y a problem befo re, because the ro tary ru ns so hot - about 1100 degrees Centigrade. Heat buildup was causing the rear suspens io n linkages to seize up, which obvio usly affected th e ha nd ling adversely as well ," Symmons said. "There are lots of o ther detail changes pl anned, but one th ing we won't be doing is building a bik e to go raci ng in the World Superbike Series - we'd have to homologate our forth-coming new cha ssis to be com- Peak horsepower, a claimed 140, is reached at 10,500 rpm, bu t our tester said "the bike seemed happiest" at 11,000 rpm. ers fro m Dunlop to Michelin du e to some inconsisten cies in the supply of rubber we' d been getting , and the extra . grip of th e Michelin rear definitely exposed a chassis problem by emp hasizing the lack of weight on the front wh eel which we can o nly comp letely resolv e by building a new chassis whi ch addresses the peculiarities of the rotary engine effectively. Ron Will iams is already designing that frame, which we' ll be racing with in 1991. We will al so hav e a new eng ine ba sed on the P55 unit in the F-I road bike which will have th e six speed Yamaha ' gearbox - . we've checked, and th e close-ratio FZR cluster fits ni cely and I hope also a gear primary drive. Because the Yam ah a gearbox ha s only two shafts (o u tpu t and inp ut) ra ther than three as on o ur present unit, we'll turn the engine round 180 degrees as on the F-I, so that it will th erefore run in th e opposite direction to pres ently, which will also improve the handling, as Honda found with the NSR5oo, as well as allow us to site the inlet and exha ust ports at the front of th e engine which will improve carbura tion and allow a better exha ust run. "Finally, we'll also be abl e to control heat ab sorption better with the new petitive, and there's obviously no ho pe of a sma ll com pa ny like o urs building 200 customer versions in ti me - 50, maybe; 200, no. So for '9 1 we plan to cont est the TT F-I FIM Cup aga in as well as the major British events and ma ybe a co up le more races aboard than we did this year, wh ile hopefu lly working on our Grand Pri x bike for 1992." Sounds like the small but dedicate d staff of just nine people in the Norton race shop - hardly the megabuc effort their outwardly professional race track presence would seem to indicate - wi ll have their hands full this winter. But ho w does Barry Symmons view the 1990 season just ended, in view of the criticism he's attracted from at least hi s erstwhi le colleague Brian Cri ghton that Norton has go ne backwards, no t forwards, th is year? "There's a simple answer to thai, in terms of statistics," Symmons replies. " My brief when I joined Norton was to provide a proper race organization and especially to improve reliability. It 's true that in 1990 u p to the end of August we'd 6nlywon 11.84% of the races we'd entered as against 15% in 1989, for the reasons stated already, b ut whereas in 1989 Norton retired in 27% of their races wi th mechanical problems (T revor Nation alone broke down in over 70% of hi s rides), this season we'r e down to 5% non-finishes, and th at 's a big improvement we can all be proud of, especially as for budgetary reasons we're racing the sam e bik es this year we were last. If we can ach ieve the sam e 'sort of reli ability with ou r new ma chines next seaso n and hope; full y the same results o r better, I think we'll have a strong basis to bu ild on for go ing G P raci ng in 1992." So, the bottom line is th at Norton recognizes they mad e a tactical erro r by goi ng raci ng this season wi th the same bikes as last seaso n, a flawed bu t fleet rotary racer that has still enjoyed a remarkable degree of success in 1990 in the increasingly competitive British scene. But by the time this became apparent , it was too late to do anything about it. In terms of overa ll compar] ison with a modern 500 V4, the j ury>' still o ut on the Norton ro tary , but t he performance of their new bike next seaso n will pro vide a more telling pointer to 1992 and the hopefu l debut of the first works No rto n to race in the 500 G Ps since 1955. CN Specifications Norton RCW588 Engine type Water-cooled twin-rotor rotary Bore x stroke 2 x 294cc swept volum e trochoidal chambers (16em x 11 cm) Displacement 588cc (rated as 999.6cc twin by FIM for 'IT F-I racing und er 1.7:1 , rotary factori sation rule, currently applicableu • Horsepower 140bhp at 10,500 rpm at gearbox' • Compression ratio : 9.2:1 • Carburetor 2 x 36 mm Amal smoo thbore' Igni tion Nort on hall-effect triggered cm Gearbox 5-speed with duplex chain primary Clutch 20-plate dry multiplate with sintered bronze friction plate 'a nd diaph ragm spring Chassis Spondon fabricated al uminium twin-spar frame Front suspension White Power inverted telescopic forks (54 mm outer/ uppe r tubes/41 mm inner/lower) Rear suspension .. .. . Fabri cated alloy swingarrn with sing le White Power unit and rising-rate linkage Wheelbase 54.5 in.ll385 mm Rake 23 degrees Front brakes 2 x 310 mm PVM cast iron discs with four-piston AP caliper Rear brakes 1 x 210 mm PVM cast iron disc with two-piston Brembo caliper Front wheel/tire 12/60 -17 Michelin radial on 3.50 in. PVM wheel Rear wheel/tire 15/6 1-17 Michelin radial on 6.00 in. PVM wheel Weight. ' : 341 lb. : Weight distribution: : 52/ 48% Year of construction .. ' 1989 Top speed , .. .. .... . .. . •........ . 189 mph

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