Cycle News - Archive Issues - 1990's

ZXR launch, then gues t riders Rob Phillis and Michael Dowson recorded lap times in the 1:37 bracket, just dropping into the 36s occasionally. Newly crowned World Superbike cha mp Scott Russell and '94 tea mmate Terry Rym er , w ho were on hand at the launch, were able to record similar times (nearly three years later), but on a bike which claims over 30 horsepower more than the '91 lO7-horsepower ZXR750J (a nd 18 h p mo re than the ZXR75OR) yet with only 22 pounds more weight. And remember that the '9 1 ZXR750 had the "rigid " rear suspension link. A FRUSTRATING TIME There can be no doubt the ZX-9R has more mid-range grunt and top-end speed tha n the ZXR750 . Rymer and Russell were reaching 149 mph in fifth gear before the fast right-hand kink up Shah Alam 's back straight, yet both the guest riders and the fastest jou rn ali sts were unable to better the respective lap times set nearl y three years ago. The bes t journalist times in '91 we re Tech talk generally in the 1:41 bracket, with a couple dipping into the high 405. Only couple of scribes were able to approach the same times this time around. "The ZX-9R is n ot a tr ack bike," echoed the Kawasaki engineers. • "The tires are for road use and not the rac e track:' sai d th e Brid gestone en gineers. "The pressures are set for roa d use," they added. "If you are having handlin g problems th en there is enough ad justmen t in the suspension to fine-tune the bike," opined the Kawasaki engineers. Well, that may be true, but why were we not allowed to carry out any adjustments to set the bike up for track use? In two days of track testing, I could not even get the Kawasaki engineers to change the tire pressures, despite advice from th e Bridgestone technicians that the road-recommended 35 psi (front) and 41 psi (rear) was too high. The rear tire's track perfo rmance was certainly criticized heavily at the follow-up press conference. Th e Z X-9R ' s rear s uspensio n also came in for hefty cri ticism at the track, a with too much initial sa g (Ka wasaki's baseline setting is sup posedly for lOmm sag) and lack of spring preload . This led to excessive rear-end squat under acceleration off the turns, which unbalanced the bike and further tortured the rear rubbe r. Russell's entry onto the front straight on his demo laps was adequate testimony to that. SO WHATS THE ANSWER? The quick fix was to immediately turn the rear compression damping up to full, which made th ings better by slowi ng down the rate of rear-end squat. But the preferred solution lay in increasin g the rea r preload, and then adding m ore rebound damping to compensate. Unfo . tunately, the standard tool kit doe s make qu ick pre load adjustmen t viable it's a thr eaded collar arrangement th at requires a hammer and punch - and witho u t the tools a nd cooperation of th e Kawasaki mecha nic s nothing could be done. "There was not enough time to allow for individual adjustments at the track," compound, w hile the rear has one aramid belt, a harder compound and a large sidewall bead-filler to limit flex. Street p ressures recom men ded by Kaw asa ki are 35psi and 41psi respectively, but for track use Yabuta recommends 33psi and 34psi, dropping to 30psi and 32psi for ligh ter riders and/ or cooler conditions. (Unfortunately Kawasaki engineers a t the Shah Alam tes t sessions would not allow pressures to be changed.) The Ninja's fai ring is made from A BS, with th ree color combina tions offered :cand y red/grey; teal green/ grey; and lime green/white/violet. The U.S., like Australia and the United Kingdom, will miss out on the combination halogen lam p and projec tor-type headlight which graces the Euro pean models (as shown in some photos). Instead, the U.S. will get a normal fu ll halogen unit with 60/55W output, wi th the small light above the hea dlight on the Euro-spec models repl aced by an airvent.The fuel tank holds 5.2 gallons, with the pe tcock offering a reserve position. Brake an d clutch levers are four-position adjustable, and the instrument console hou ses spee do me ter, electronic tachometer, and fuelandtemperature gauges. ;; ThepjJ.li()tlseat . can be removed (a oi f "fiddly)1 fo r access .to a storage co mpa r tmen t designed to accommod ate a U-type lock. Claimed dry weight of the ZX9R is 473 pounds, which places it 22 pounds above the ZX R and 39 pounds below the ZX-l1. "The all-new ZX -9R liquid cooled , in-lin e four engine has been developed to produce class-leading power and torque with the reliability Kawasaki is known for ." Those are the opening words in the Kawasaki press release on the ZX-9R's powerplant, but they're not quite as accurate as would first appear. You see, the ZX-9R's enginE;has more in common with the '93 and '94 ZXR750 po werplant than it is "all new". After all, both engines are liquid-eooled DOHC fours. Both engines run 'identical compression ratios (11.5:1), have identical valve timing arid iden tical internal gear ratios. In fact,the.z?(-9R said the Kawasaki engineers later. "It's so meth ing you can ex peri me n t w it h when you return to your coun tries," they added. One has to ask the question why we then spent two full days at a race circuit on a bike which wasn't all owed to be ad justed to s u it the individual rid er requirements? You've no idea how frustrating the whole thing was - her e we were with Kawasaki's new pride and joy, surrounded by hordes of proud Japanese engineers, ye t w e cou ldn 't carry out minor adjustments to fine-tune the bike to our own requirements for the track. E v e n rid er weights varied from around 120 pounds to over 220 pounds! And remember, we'd yet to sample the ZX-9R in any other environment. Th e on ly journalist to "get away" with the necessary ad justm e nts wa s Bertrand Sebilaut from the French magazine Moto Journal, but he had the added "p u ll" of Kawasak i Fra nce race team bo ss Christian Bourgeois in the French conti ngen t's co rne r. They simply comma n d eere d a b ik e and w ith tw ice as

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