Valentino Rossi’s crew chief Jerry Burgess says he is looking forward to gauging the performance of a new Yamaha Y
ZR-M1 engine next week in Brno.
A new improved four-cylinder motor is expected to be rolled a test session after the Czech Republic MotoGP in Brno, with the new motor is widely anticipated to feature pneumatic valves to increase rpm and top speed performance.
Yamaha has been working on the engine in Japan for months in a bid to close the gap on rivals Ducati, with the Bologna factory’s GP7 easily the fastest bike on the new 800cc grid.
The 28-year-old goes into the Brno clash trailing world championship leader Casey Stoner by a massive 44-points following the Aussie’s dominant victory in the American MotoGP clash before the summer break.
Yamaha engineers are happy with reliability tests in Japan and are now readying the in-line four-cylinder for Fiat Yamaha rider Valentino Rossi to evaluate for the critical championship run in from the beginning of September.
Jerry Burgess told MCN: “All this year our bike has been absolutely spot on. We've hardly been off the front row of the grid, we've been qualifying on pole.
“The bike just needs a little bit more push, that's all it needs. It's got the chassis, it's got the character. We just need a nano’s help on the engine.”
Valentino Rossi’s current Yamaha, which has won three races so far in 2007, is using a conventional spring valve system.
And Jerry Burgess said: “I think we are limited by springs. With springs you are limited to how far you can open the valves.
“With pneumatics you can open them a bit more, and a racing engine needs an extra amount of valve lift to be optimum. Anything else is a compromise, so we've got to look at what's the best.
“The message is there, that the teams that have different valve systems are going a little bit better than us in terms of speed. Certainly Ducati's not winning only because of Desmodromic valves, but certainly we've seen a massive improvement in the Suzuki and the Kawasaki who do have pneumatic valves.
“Clearly our engine is very, very good. The character gets us around on a qualifying lap better than anyone, so we then have to make it where the other guys can't use their superior skills of passing on the straight.”
Jerry Burgess said the incredible top speed and horsepower advantage held by Ducati and Rossi’s title rival Casey Stoner had proved even more critical in 2007.
“As we’ve seen not having the engine is far more of a disadvantage than it has been in other years. These bikes corner so well that there is no real opportunity for riders to make passes in the corners,” said Jerry Burgess.
“It’s much more difficult even for someone with the skills of Valentino because the other guys’ bike speed is that much higher. The engine is a very important part of it, particularly over the distance of the race.
And he added: “We have got a great rider and a great bike but we are perhaps lacking a bit of push from the engine.”
