Cycle News - Archive Issues - 1990's

~ TEST Honda NSR500 ~ nimble in slow turns, like the series of slow corners climbing the hill behind the pits; it seems to hold a tighter line better, without washing out the front end at the apex, especially when you start to' feed the power on. It also turns into the corner better. I have no idea if this is due to the new engine configuration, unless perhaps the 294 degrees of engine 'down time' allows the bike to turn better because the back wheel isn't trying to drive it straight ahead under more constant power delivery pulses, but one thing's for sure: this is definitely the best handling 500 Honda out of. the eight I've ridden to date. It also stops as well as any, in spite of the extra 33 Ibs. it carries compared to the 1990 version which was the last NSR500 I rode in the dry: last season's minimum weight increase for 'the 500cc class posed brake manufacturers some big problems, which in Honda's case they resolved by switching to 290mm Brembo carbonicarbon front brakes on Doohan's bike. These give the usual phenomenal stopping power you expect from the black brakes, but with other notable factors as well. For a start, the brakes stay warm enough under those G:arbon fiber shrouds to give maximum braking instantly even at the end of the two long Suzuka straights. Secondly, unlike AP carbon brakes (from whom Brembo sources their materials) the Honda's black brakes didn't gradually servo- themselves into max stop mode after the initial squeeze: they worked hard from the very first, and for someone who's become used to using the brakes pretty hard after a couple of seasons racing a Bimota Tesi, I have to say the Honda brakes brilliantly. But also important is the fact that there's more senstivity' than I expected without the steel! carbon 'Gardner cocktail"(one of each kind of disc); running too hard into one of those slow uphill turns and needing to cram off a little speed could be easily be done by just a light finger's pressure on the lev,er - again" something I've not experienced before with black brakes. Brembo have obviously done a lot of development in this vital area, which moreover is surely a further factor in the NSR's lighter, more precise steering - thanks to'the reduced gyroscopic effect of the black brakes. I've been told how this is supposed to make a difference, but never experienced it for myself - until now. However, I have to say another factor in the NSR's good braking performance - and at the speeds this bike is capable of, you need to be supersure of stopping safely! - is tl,1e surprising amount of engine braking there is on offer, more than I can remember from any two-stroke, even a Rotax tandem-twin, which of course had both pistons rising and falling together. On the NSR, with four pistons doing the same almost in unison, plus a very high compression ratio that HRC staff was unwilling to reveal, you can feel the engine braking effect especially slowing down for the chicane, and again into the hairpin, where I found myself going in deeper and harder than ever before. I also found that going faster round turns was easier without using a lot of angle, because since the bike is easier to fire up out of a corner thanks to the more friendly power delivery, you can get it upright earlier and switch the power on harder and sooner. Then, hold on tight - Very tight! The Doohan bike I was riding (and Criville's similar machine) had the engine located higher in the chassis than, on Gardner's special version, (Above) Alan Cathcart puts Michael Doohan's Honda NSR500 though its paces. (Left) The four exhaust pipes stared at the competition throughout most of the 1992 season. (Below) Doohan's cockpit. proof of how hard he must use it if it needs extra cooling in that way. HRC boss Yoichi Oguma has gone on record as saying that winning the 500cc World Championship is Honda's major goal in two-wheeled competition, followed by the Suzuka 8Hours and the 250cc World Championship. Two out of three in '91 and' again in '92 ain't bad - but it was, the big one that eluded them both times, and again in 1990. After failing to recapture the 500cc crown last season (and this breaking a decadelong tradition of alternating it with their ,bitter Yamaha rivals), Oguma says Honda decided drastic action was necessary, so instead of confining the task of coming up with a new design for the 500cc class to the NSR500 project engineers, they threw it open to everyone working at HRC. Seven designs were deemed worthy of further consideration, of which two were promising enough to translate into metal. The Big Bang engine was the one that was selected - but Oguma says that the other design might still, make an appearance in the future.' If it does, Honda must hope that it represents as dramatic an improvement in translating the power their engines have traditionally delivered to the road as the Big Bang NSR500' undoubtedly represents. By building a better Ducati (or Harley); Honda took GP technology into a new age in 1992: too bad they didn't get the reward they CN deserved. While Cycle News believes the foregoing test reliable, it is the opinion of the reviewer only and should not be relied upon in determining the performance or safety of the vehicle. The reader should make his or her own ~nvestigation. where the engine is lower to make the bike more controllable under his more, er, violent riding style. But with the higher engine there's more weight transference under braking and accelerating, which I'd have thought would improve front end grip into turns, and traction out of them. Maybe Wayne just likes to have both ends wobbling around - simultaneouslyl But the Doohan bike also has a very rational riding position, with just the right amount of body weight on your arms, and lots of room to move about in the seat, in spite of the fact that the bike feels relatively compact for a 500 V4. And of course, all the controls are as light and finely tuned as you expect from a Honda works racer, reflecting the thousands of man-hours that go into to hand-crafting each of these million-dollar machines. The four 36mm dual-body Keihins nestling behind the massive carbon fiber ducts have a precise, light throttle action worthy of the fuel injector butterflies that will surely replace them soon Honda admits to having EFI already under development on the 500 as well as the 250 which has already raced with it. The three-position handlebar switch used in the early part of the season made some suspect EFI was already fitted, but HRC staff claims this was simply to experiment with a choice of three different advance curves for the ignition - something Ducati already tried two seasons ago on their (fuel-injected!) 8-valve desmos. EFI is coming to the GP world soon, for sure: only not just yet ... One avant-garde feature that did appear this season in GP racing was semi-active suspension, courtesy of both Ohlins (Roberts Yamaha) and White Power (Aprilia). Honda's suspension suppliers Showa almost certainly have such a system under development themselves, but so far it hasn't appeared on the NSR500 in public, probably for pragmatic reasons. I couldn't fault the NSR's suspension setup in turns or over bumps - it handled the notorious Suzuka Sh~kes on the fast righthander past the pits perfectly, just shaking its head a little when I hit the bump under full power, cranked over. As a sign of how far Honda's overall handling package has come in just three years since the last time they won the 500cc title, courtesy of Eddie Lawson and a bike that needed to be run on a maximum 'steering damper setting to stop itself twisting into knots, Doohan's bike uses very little steering damper, in turn making it lighter-steering as well as easier to get through that godawful chicane. Honda basically ran the same chassis setup all season, with only some aerodynamic updates as the season progressed. The basic engine was updated twice, though, once at Hockenheim for more top end speed (in spite of which it was .62 mph slower than the 1991 bike - but at 190 mph, who's counting?), and again at Kyalami where a special version was concocted to concentrate more power in the top rpm 'range, so as to save Doohan having to change gear so often after his leg injuries. Interesting to note the reason he gave for not being able to keep on the pace in that race, after such a brilliant qualifying time: he couldn't use the rear brake. Looking at the HRC-made rear I disc on his bike, I saw to' my surprise it was a ventilated steel rotor, Specifications Honda NSR500 Engine type Water-cooled, 112-degree V-4, crankcase reed-valve, two-stroke with computerized electronic power valve Dimensions 54 x 54.6mm Capacity 499cc Output ; Over 175 bhp at 12,500 rpm (at crankshaft) .4 x dual-body Carburetion 36mm Keihin with electronic , power valve sensor Ignition Pre-programmable computerized electronic CDI Gearbox 6-speed extractable Clutch '.. Multiplate dry Chassis Extruded aluminium twin-spar frame with fabricated swingarm and steering head pivots Front suspension ..... 43mm Showa inverted telescopic forks with carbon fiber sliders Rear suspension Fabricated aluminium swingarm with Pro-Link rising rate linkage and Showa shock with titanium spring Head angle 22.5° nail., 95mm Wheelbase 1405mm 28B-Ib. Weight Weight distribution 55/45% Front brakes .... 2 x 290mm Brembo carbon discs with four-piston Brembo calipers Rear brakes 1 x 196mm HRC ventilated steel disc with two-piston HRC caliper Frontwheelltire 12/60-17 Michelin radial on 3.50" HRC wheel Rear wheel/tire 18/67-17 Michelin radial on 6.00" HRC wheel Top speed 190 mph (Hockenheim) I

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