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MotoGP Tech Update: Candy For Everyone The new-style breather pipe o n the Yamaha Ml . The old-style pipe, still favored by Valentino Rossi. The traditional supply of new parts I turned up at Brno fo r the Czech Republic Grand Prix, and Honda had clearly spent the most - with engines, exhaust systems, seat units and nose cones available for all their top riders. If there is a clear pecking order in the satellite teams, then It seems that Sete Gibernau and Max Biaggi are at the top of that order, having access to the full to p-o ft he-line HRC works kit, while Colin Edwards and Makoto Tamada are making do with new nose cones and previous -gen- eration works exhaust systems. New parts, though, are not necessarily what you want at a race with such variable weather as what was experienced at the Czech Republic GP. By early Friday morning, both Biagg! and Gibernau had one of their RCV211 V's converted fully to the new spec. They had both received the modified swingarm-pivot chassis fo r Sachsenring. but now they had the rest of the parts as used by Alex Barros for the last two races. Biaggi, who has been quite vocal about not having access to the latest parts , chose to embrace the new technology immediately. He got on a bike set up to the new spec and used it all of Friday, and by Saturday morning both his bikes had been converted. At Telefonica Movistar Honda Pons , however, Gibernau had decided that it was a case of "bett er the devil you know," and the new bike sat on its stands all the way through Friday as he used his old bike to great effect in the changeable conditions. By Saturday morning, the team had con verted the "new" spec bike back to the old setup, making sure the Spaniard had two bikes he knew and trusted for the tricky job of qualifying in the wet. New parts need time to set up , both for the riders' feel and to make sure they are reliable, and the record will show that Biaggi took the gamble and suffered , and that Gibernau played the racer's card a little more cautiously and came away on top. Monday testing after the race would seem to be Gibernau's best 8 time to get used to his new kit. Down at Valentino Rossi's garage, something was clearly up . Rossi's Gauloi se s Fonuna Yamaha team has spent more time with the garage door shut than any other this yea r, and at Brno they outdid themselves, with the garage door coming down any time anybody with a camera came too close. Over the last few races, Yamaha has int roduced subtly different fairings with revised inner pieces that seem to allow more air to flow o ut of the radiator. Additio nally a , small bulge that has covered the crankcase breather system pipes for the last two years has bee n move d, and to allow this to happen, the breather pipe has been rerouted. Instead of a very simple straight pipe fro m crankcase breather to exhaust, the complicated new pipe bends in and around the frame spar. We are to ld this is because the sponsors woul d like their name clearly spelled out, and the bulge means the Gauloises name has a bump in the " 0." For some reason, however, Rossi's team has not adopted the change . It may be because he has a very careful crew chief who realizes the simple pipe with only two bends in it has been perfectly reliable in service. Je remy Burgess doesn't want any unnecessary new parts on the bike. Or it may be because there simply isn't room for the new pipe on Rossi's motorcycle. Rumors are rife that the Italian has a different engine than the other Yamaha men. Logically, Yamaha would have to rev the engine more to make more power, and the classic way so do this would be to reduce the stroke and SEPTEMBER 8, 2004 • C YC LE NEWS increase the bore to allow th e engine to rev more while do ing so safely. An increasedbo re engine might just be a little wider than the old motor, cutt ing off the space the revised crankcase breather system needs. The pipe that has been rerouted has bee n on the engine since the ea rly days, and it allows Yamaha to use the negative pres sure in the ex haust system to pump down the pressure under the pistons in the crankcase, making it easier for the pistons to come down. By re ducing the amount of work, the engine thusly makes mo re power. It's an old NASCAR idea that can't be used on street bikes or in superbike racing because their rules re quire the crankcase breath ers to exit into the alrboxes. In Mo toGp' however, there is no such restriction. The idea w ill be even more important with the 2004 Yamaha firing o rder likely to pressurize the crankcases even more than last year. Yamaha has use d this system before, with it appearing on their prototype YZ426 four-stro ke mo toc rosse r a few years ago. There were many other small changes being tried out in the Czech Republic. Kawasaki was trying out new lightweight crankshafts, but breakages on its "heavy crank" engines and the weather conditions dearly caught them out . Lightweight cranks allow the bikes to rev up quicker out of corners and theoretically allow them to also change direction more easily. But they also have a tendency to spin up more easily, possibly more than the rear-tire traction control wo uld like. In the dry, you co uld get away with it, but in the wet the end result is that the engine spins the tire and the tra ction con tro l cuts back power trying to regain grip. and the motorcycle goes very slowly. As soon as it rained, the Kawasakis duly went backward down the grid . Kawasaki tried its heart out wit h some fairly serious work going on lat e into the night on Friday and Saturday, with a much better result being o bvious in the dry warm-up on Sunday. Aprilia showed up with a new swingarm, a lot less than the new gearbox and chassis we have all been patiently waiting fo r, but they are definite ly int roduci ng a new motorcycle in stages. The new swinga rm is des igned to allow an "under the seat " exhaust system and is also fitted with mounting points fo r a shock absorber to be fitted that is mounted to the swingarm at the top. The new piece wasn't 40th Anniversary pop ular with the riders, though, with complaints that it flexed under power. Possibly, however, the takeover of Aprilia by Piaggio will allow the new chassis and gearbox to come out be fore the end of the season. Proton is promising to test the KTMengined derivative of their bike at Estoril after the Gp, but in the meantime it is cornmitted to getting through the rest of this year with thei r problematic V-five. New carbon-fiber engine sidecovers were de bute d at Brno, with team manager Chuck Aksland confirming that development would continue through the end of the year. Suzuki and Ducatl seemed to be content to carry on with the same kits they had at Doningto n, but then again the bikes are very different already to what they started the year wit h. The important thing for those two teams is to just have more time getting used to the stu ff they already have . Nell Spalding The Kawasaki crew put in long hours a t the Czech Republic Grand Prix . Sete Gibernau's ne w -sp ec Honda sat unused at Brno .