Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/128309
ROSSI RIDES! o the waiting is over, and now w e know. About Valentino Rossi and his first ride on a Y amaha, I mean . At his first official atte mpt , he set a Sepa ng lap t ime that was ster t han eve rybody else so far except ax Biaggi and Sete Glbernau , both on ondas, w ith which they are well famili r. a ut it's no great revelation t hat Rossi can p fast on a Yamaha, just like e could on a Honda. It's hardly surprising. Rossi , after all, Rossi, and supremegifted . And don't forget that ther Y amaha riders managed he occasional fast lap last once. And a clout of more than 70 horsepower. Ducati tried some thing similar with its first experimental Desmosedi ci V-four, firing it off with two pots at once so it mimicked the beat and the sound of its highly successful V-twins. The so-called Twin-Pulse was put away for the rest of the year after proving prone to breaking itse lf to pieces internally. nating top ic for motor cycle anoraks everywhere . And also fo r Valentino, who is certainly no tec hnical illiterate. And at this stage anothe r item of waitand-see, in the eve r-growing jigsaw, we will also have to wait and see how long it will take Rossi and his crew to take that difficult step from running a few fast Yamaha laps to putt ing them together for full race distance. But this is o nly one possibility, and a relatively simple o ne , sticking with a conventional two -up!two-dow n four-cylinder crankshaft timing. Yamaha might, howe ver, be pioneering something really new and differen t, abandon ing convention to move the timing of the cylinders away from t he st rictly symmetrical. In this way, it can emulate a V-four's firing inte rvals, if not quite those of Honda's V-fIVe. And it will not only change the way the bike sounds, but also the whole way it handles. As demonstrated by the Big Bang two-stro ke revolution of 1992, which rew rot e the rules of traction and tire performance pretty much overnight. It wo uld be an interesting and possibly hugely fruitful experiment, as we ll as a fasci- fire together, and likewise two and three. That 's just a matte r of retiming the cams and ignition. Then the four wou ld emulate a 180-degree parallel twin, a familiar configuration with a distinctive off-beat pulse. There would of course be some difficulties - most particularly in making the casings and transmission strong enough to cope with two 247.Scc cylinders going off at And whether Yamaha's engineering will provide strength and reliability at the first atte mpt. And wheth er Yam aha will abandon its trademark five-valve cylinder head for more conventional four-valve, as it quietly did with its F I car engine. These are still the earliest of days, and it's important to remember that Valentino's highly impressive Yamaha deb ut was only the first test. (Unless you believe ugly rumors that he was quietly spirited to Japan to break the midwinte r testing ban.) He and his crew will doubtless have more to come as they addre ss the gap of about half a seco nd to the best times set by the to p Hondas at the same track earlier last week. By the same token, Honda also has more to ear... and sometimes more han just the one lap. In fact, at reseason testing, Alex Barros so quick that some even ipped him for the title. Until e first race, anyway. Twelve onths later he was desperate o escape the MI and get back on a Honda. The discovery is someth ing else - that Yamaha, as I've long suspected and have several times written, lured Rossi by more than merely titillating his spirit of adventure. It must also have promised him rad ical changes to t he MI Y amah a. Th e quite differe nt exhaust note of the bike Rossi rode in the latter part of his first te sts at Sepang provided clear aural evidence that it has done so. Secrecy re igned at the tests, and security w as tight. All that Y amaha's me n wou ld admit to was that the new bike (o ne of two versions, the oth er still to follow) had "a different firing order." Th is innocent-sou nd- ing phrase carries a wea lth of technical implications. It's probably safe to assume that the MI is still an in-line four and that Yamaha hasn't already done wha t I only half-jokingly suggested before and simply built Valentino a V-five Ho nda clone . So what changes in firing ord er are possible with an in-line four? It wou ldn't be too difficult to Big Bang it, doubling up so that cylinders one and four www.cyclenews.com come. So I'll fall back on a com ment from one of the other teamsters test ing at Sepang last week - Suzuki manager Garry Taylor : ''Asking about testing is a bit like asking Michelangelo how good the finished painting on t he Sistine chapel ceiling will be, whe n he's still just putting up the scaffolding." eN CYCLE NEWS • FEBRUARY 4, 2004 83