Cycle News - Archive Issues - 2000's

Suzuki GSV-R MotoGP Racer on the gas, even over bumps at high speed, where the Ohlins' suspension and longer wheelbase combo really deliver. However, not all is rosy because again, like the RGV500 its chassis is derived from - the GSV-R is pretty unstable under hard braking, with notable weight transfer even with my extra kilos aboard, which sets up a weave and has the back wheel waving in the air as it repeatedly clears the deck and starts street-sweeping the tarmac while you a) try desperately to calm things down by shifting your body weight around and/or use the rear bra ke ha rd (er) to try to reverse the loads - not recommended procedure on a high compression four-stroke, but we'll come to that in a minute, b) hunt equally desperately for the line you'd chosen for the turn coming up, and c) hope and pray, with the accent on the latter, that you really will get it stopped without attacking the kitty litter you seem to be aiming straight at. If at the same time as all this is happening - and it's surely a direct consequence of the incredibly effective braking delivered by the carbon/carbon Brembo front discs and their radial four-pot calipers which represent one of the key differences between this V4 MotoGP bike and a good Superbike, which doesn't have anything like such explosive stopping power - you start getting the rear wheel hopping because you're using engine braking as well, which the slipper clutch isn't handling capably enough, then I can quite see this would be a recipe for disaster. This is what Kenny Roberts had to endure for the first part of the season until Suzuki went to a new clutch design. But, fortunately, I didn't have this problem. After my first four or five laps while I was riding the GSV-R on autopilot, trying to work what the direction of the circuit and where the damp patches were, I suddenly woke up and remembered what I was riding - the bike with a clutch that's got a mind of its own, right? Wrong, as a harder compound to make it last the distance, which, conversely, would give less grip in the early stages of a race. At the same time, the Suzuki's power feels as if it flattens out at higher revs, which might explain the apparent lack of explosive Honda-style top speed - it just seems to stop pulling really hard over 13,000 rpm. Less bottom end, snappier midrange engine acceleration and more power and revs up top, please, Kamomiya-san! I'm sure Suzuki's winter development will be focused on moving the power up the rev scale, perhaps with a shorterstroke engine format than they have at present. They can afford to give quite a bit away lower down to do so, and while they're at it, I'd expect them to want to find another 5001000 revs even higher than at present, to improve top end power and, with it, top speed. But the engine basics are surely there already. They simply need refinement. Same thing for the chassis, which has largely succeeded in replicating the sweet steering of the RGV500 two-stroke frame it's based on, while also repeating its deficiencies. Like the stroker, the GSV-R changes direction well in tight turns, though perhaps because of the four-stroke engine's increased rotating crankshaft mass compared to its twostroke predecessor, you do have to work at lifting it from side to side in any of the Sepang chicanes. It has a very balanced feel, in spite of the heavier engine and 25mm longer wheelbase than the RGV500, and the revised chassis geometry this brings with it. That's further underlined by the Suzuki's stable high-speed handling: it doesn't start leaping about when it runs over the car-induced ripples in the Sepang tarmac as it's powered through the fast Esses and lined up for the next slow right on to the start of the back straight. Nor does it push the front wheel under power rounding the long, fast left before that. The Suzuki stays planted and holds the line chosen for it when 18 DECEMBER 1 1. 2002' cue • "" ftevvs four-stroke experts Kevin Schwantz and John Hopkins agreed later when we marked the Suzuki's scorecard: the GSV-R's original sprag-style slipper clutch may have been less than perfect, but the new ramp-type one we tested which was introduced from Estoril on is beypnd criticism': provided you ride the GSV-R like a fourstroke and blip the throttle slightly between changes. That's second nature to the likes of Hopper or Kevin, who grew up racing engines with valves that go up and down rather than round and round - as well as to someone like me who spent a quarter century racing 'diesels,' especially of the twin-cylinder persuasion. You just never dreamed of standing on the brakes and stomping the gear lever down three gears all at the same time as many do on a twostroke - but that's what reformed 500GP riders like Team Suzuki's duo last season wanted to do at first; and that's why a bike which, because of its chassis behavior, was already flighty under braking, became such a swine until they got Suzuki to remedy things, at least partially. It's the way of the four-stroke world, and it'll be interesting to see how proven fourstroke riders like Hopkins or Colin Edwards or Troy Bayliss go next season against the serried ranks of reformed ring-dingers and whether they'll experience the same problem this year's MotoGP riders have complained about on the way into turns. The jury's out till we evaluate them in action - but for the time being I have to say [ thought the GSV-R transmission package was one of its strong points and that the reason the bike gets flighty under heavy braking is chassis- rather than engine-related. [ did try riding it Kenny's way for a few laps, stuffing it down though the gears without using the clutch and relying instead on the engine management gizmo his chief mechanic Bob Toomey and his colleagues have dreamed up to help him: the self-blipping downshift mechanism. Using this on an engine as unmistakably fourstroke as the gutsy-sounding, growly Suzuki seemed at first like cruel and unsual punishment to the gearbox, especially changing down into second gear or especially hitting bottom once per lap at Sepang, when it seemed I had to force the gear home against its will. But after a while I realized that Toomey & Co. have also set the electronics up so that you need to sort of preload the shift mechanism with your toe, which makes the shift action less harsh, presumably because you're making it anticipate the change and setting the engine management's autoblip in motion. Weird - but wonderful. This is all pretty important because of the Suzuki's lack of top- end speed in its present form, making it the slowest of the new MotoGP contenders. This means that KR has to go big on keeping up turn speed by staying on the power as long as possible and braking later than any.one else, too, so as to max out turn speed ·and maintain hard-earned momentum. If you can't trail-brake into the apex because your rear wheel's hopping abaut under engine braking or, more likely, you've braked so hard the resultant massive weight transfer has upset the bike's stability, then Houston, we have a problem. That's another thing I'm sure Suzuki will be working on for next season, having already made a significant improvement, says KR, with their new clutch design, which allowed him to register his best three places of the season (4th, 3rd and 6th) in the three races after they introduced it in Portugal. Suzuki's pragmatic decision to go racing with their work-in-progress MotoGP prototype this past season has definitely paid off - they're much further along the R&D trail as a result, and in consequence have the makings of an excellent motorcycle for next season, which I'm sure their Team America rider duo will make the best of. Watch this space - and expect this bike's successor to be a contender for top honors, because there's no way someone as astute and expert as Kenny Roberts would have signed up with Suzuki for another two seasons if he wasn't convinced of that, too! SUZUKI GSV·R TECHNICAL: WHY AND WHEREFDRE You wouldn't have blamed them for doing it, if they had. Having decided to replace their world title-winning RGV500 two-stroke with a four-stroke contender for the new MotoGP class, and having begun work on it via computer simulation and pre-design study only in February 2001 - a good two years or more after Honda and Yamaha started on theirs - Suzuki might have been forgiven for taking a short cut to the starting grid by developing a bigger and/or better MotoGP version of their in-line four-cylinder GSX-R750 Superbike or ultrasports GSX-Rl000 streetbike. After all, with three AMA Superbike titles, the World Endurance and one Japanese SBK Championship crown to its credit, the GSX-R750 had become the proven benchmark of the four-cylinder Superbike class, and the new GSXR 1000 was about to start streetsweeping the maxisports class, so it would have been understandable if Suzuki's compact Race Department by some way the smallest of the three Japanese manufacturers who've traditionally contested GP racing over the past two decades, with just 30

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