Cycle News - Archive Issues - 1990's

Same with the engine, too. The XR79 version of Suzuki' s 7D-degree V-four is cl osely based on the Big Bang XR78 which was introduced in May of 1992. Suzuki was the first of Honda 's rivals to reac t to the Sound of Suzuka, w hen the first N R500 w ith a cl o sed-up firin g order alerted the rest of the GP world to the im p roved tr a ction and increa se d rideability offered by the New Order of two-stroke race engineering. The title-winning '93 engine is esse ntially unchan ged, says Sh enton, apart fro m switching to magnesium crankcases this season instead of the aluminium ones used befor e. This saves abou t 4.4 pounds in weight, allowing the team to ad d stiffness in other areas - better bearings in the swingarm p ivot, for example, or an improved linkage for the rear shock - as well as making improvements that cost weight, like adding an electronic speed-shifter and smoothing out the shift linkage. "Our main aim was to make the bike as user-friendly as possible," Shenton said, "with a power delivery that's more linear than progressive . Ideally, half a tum of the throttle should mean half the available power, at those revs, delivered to the back wheel. It's all a process of re fi n e m e n t we're aim ing at, which Suzuki has gone along with 100%. And the results are there to see - look at the way Alex was able to adapt to the bike so quickly that he almost won the fourth GP on it here at Jerez, if he hadn't gotten overly enthusiastic wi th the checkered flag in sight." A user-friendly works 500? - there's a n ovel thought. And ye t...a nd ye t, the Suzuki that put Schwantz on top of the w o rl d at la st is, relatively s p ea ki n g, exactly that. Out of the four works racers from four d ifferent factories that I've ridden in the past four weeks, the Suzuki is recognizably the most refined and comp lete, yet at the same time the most rideable. It doesn't have the raw top-end power of the Honda NSRSOO, bu t it's a more confident, easier-handling bike, and a better all-round package: The Cagiva, which so greatly resembles the Suzuki, is close, but it isn't so easy to change direction with and, now that I've ridden both bikes, I know the Cagi va still lacks that vital edge in accelera tion which I thought it might finally ha ve ob taine d. And while th e re sults obtain ed by Wa yne Ra iney an d Luca Cad alora on the Ya mah as s p ea k fo r themselves, especially af ter their reputed handling problems we re reso lved by ado pti ng a ROC chass is, th e ROCfra med Big Ban g wo rks Yamaha I sampled d idn't have the top end power and a p pe tite for revs th a t the Su zuki h a s, even if it s teered a nd ha ndled just as well . By a pa tien t process of g ra dual development, the Lucky Strike team and Suzu k i e ngineers h a ve e volved th e RGV500 in to a bike that, in the form I ro de it, a n d at my ge n tle r pace, is a paragon of all-round excellence, a master of all trad es, deficient in none. There were, obviously, occasi ons when the team struggled to find the right setup to enable Schwantz a nd Barros to wield their customary magic. But a bike that can win at tracks as diverse as Eastern Creek and [ararna at one extr eme, and the Salzburgring at the other, with swoopy, sweeping Assen somewhere in the middle, not to mention its supremacy at twisty Jerez, where I sampled the RGV500 for myself, is a truly adaptable motorcycle - th e Suzuki switch-hitter. Why you can ev en, honestly, imagine riding it on the street...so long as there's a German autobahn with no speed limits close at hand, to let y ou clear the plugs out at 186 mph-plus. . This is all the more ironic in view of the fact that, for internal reasons, Suzuki race team management had to pretend, back in 1986 when they announ ced their official return to the GP arena, tha t one of their obj ectives in doing so was to develop a race-bred s u ccessor to the RGBSOO street rod, in tum derived from the RGV's square-four rotary-valve pred ecesso r which was World Champion. A fter r id ing it , the th o u g h t of an RGV 50 0 road rocket base d on Kev's World Champion GP racer is not as farfetched as you might imagine, an d certainly more than a little tasty. Do I ex aggera te ? Well, w ind th e throttle wide op en in seco nd gear exit ing the last tum before the p its at Jerez, then feel the rear of the bike squa t as the Michelin radial digs into the tarmac and listen to the deep, throaty grow l of the Big Bang motor, whose four cylinders fire in diagonal pairs (left front with right rear, then vice versa) just under 90 degrees apart, leaving over 270 degrees of down time for the tire to get a grip on things and propel you without drama out of the tum and off down the straight at speeds you can only dream of. Watch the tach needle climb from under seven grand up to 13,600 rpm in a seamless, stepless, glitch-free mode - then tell me I exaggerate. . The Suzuki has a myriad of electronic systems to help make this possible, two of which are a single guillotine-type power valve in the 8-port (five transfer /three exhaust) cylinders, and a complimentary Power Chamber variabledimension exhaust system, each with a separate motor but working in unison, electronicaUy-eontrolled by an EPROM chip and according to the throttle position, ignition curve and gear selected . It' s a mark of how re fined th e power delivery is that it's quite possible to tell when the power valve is w ide open or the Power Chamber in full po wer mode - so smoo th and linear is the transition, yet at the sa m e time so strong and meaty the power output. Suzuki started the year w ith two different engine specifications, one sharper and more hard-edged , the other smoother and easier to ride, with the same absolute top end. It's a mark of the effectiveness of Suzuki's work that both riders ended up using the more linear, more measured configuration for the last four or five races. After riding the result, you can figure out why: it's just simply more rideable, and that's as important to a Captain of the Universe like Schwantz as it is to a play-racer like me who 's pretending he' s king for a da y. " I usually co me o u t of a turn a t around 8500-9000 rp m, " said a watching Alex Barros, "but the engin e's so responsive low down, you can gas it wide open from as low as 6300 revs, and it s till accelerates well. You're using too Iowa gear and too many revs out of the last tum here, which is why the bike 's standin g o n the ba ck wheel. You must be us ing bottom gear, which we never do here - we gear it to run just the top five gears at Jerez, and som e other tracks too. There's such a w id e .p ow er band, you can do this: I usually change up at about 13,000, but it'll run to 13,800 rpm before the power falls off, if you have to." Taking Alex's advice and riding the torque curve out of turns proved this is the hot tip - but it still doesn't keep the front wheel on the ground all the time. The Suzuki is so potent and punchy, it'll whee lie in third gear quite happily. Though peak power of more than 165 bhp at the back wheel is delivered at e 12,800 rpm, a few revs higher than last season, it would run almost 1000 rpm . over tha t, as Alex predicted, if you needed to save a couple of gearchanges, . like in the twisty section after the first tum. And with Suzuki's "p re-emp tive traction control" in the bottom three gears - not true traction control like in F.... 1 car racing, where the system is triggered by the onset of wheelspin, but a ~ different kind of rid er-a id to stop it hapl-t pening in the first place - all ied to the Q) benefits of Big Bang engine design, you can catapult yourself out of turns with a ~ power that becomes addictive, all withQ) out the bike getting out of shape or the U rear wheel go ing walkabou t, ev en on Q) the standard rad ials I wa s u sing. Of course, if your name is Kevin Schwantz, a touch of acroba tic ballet as you flick the back end back in line is all par for the course, but we're talking conventional human ability in my case, not the kind of superhero who rides at 101%plus aU the time. The Suzuki "not-a-traction-control" system is another electronic system, which retards the ignition in the bottom three gears, depending on throttle position and engine rpm, and can be preprogrammed via an EPROM chip to deliver ..g Q After six years of trying, Kevin Schwantz and Suzuki finally won the SOOcc World Championship. (Below) Alan Cathcart was given the opportunity to ride . the championshipwinning RGVSOO at Jerez in Spain. (Left) After complaining about the brakes on last years bike, Cathcart came out of this years test with a completely different impression of the AP carbon brakes, thanks to a more user-friendly grade of carbon/carbon. ·" Th e best I've ever sampled," Cathcart says. 15

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