MotoGP: Valentino Rossi tests 2008 Yamaha contender in Japan

Valentino Rossi has tested a prototype version of the bike Yamaha hopes will help the Italian wrestle back the MotoGP world championship crown in 2008.

Less than 24 hours after Rossi’s disastrous 13th place in the Japanese MotoGP saw Ducati rival Casey Stoner claim his first MotoGP world title, Valentino Rossi was testing a 2008 spec YZR-M1 at the Twin Ring Motegi circuit.

The new bike features a completely new chassis and swingarm and all-new bodywork and seat unit. Valentino Rossi tested two different spec frames today, but later revealed to MCN that a 2008 pneumatic valve YZR-M1 motor wasn’t ready to test and was still undergoing development on the dyno in the Japanese factory.

He also ran the new chassis with the 2007 conventional spring valve system.
Yamaha is desperate to drastically improve the performance of its four-cylinder machine after the domination of Ducati and Casey Stoner in 2007.

Ducati has won nine races in a season that saw them become the first European factory to win a premier class crown since MV Agusta in 1974.

Yamaha and Valentino Rossi have won just four times in the opening 15 races of the season, and with the 2007 world championship already gone, the Japanese factory is adopting a more aggressive development strategy to try and close the gap on Ducati.

The 28-year-old said: “We had two new chassis to test for next year. The Yamaha guys wanted to know which way to follow and I preferred one more than another that give me some problems.

“We used the same engine that I used in the race so we could make a direct comparison with the chassis. This is the first step but already for me the chassis is not so bad. We have to work more on the engine, that is our problem. But at the moment we start like this.”

Valentino Rossi said Yamaha engineers were currently experimenting with different stiffness ratios on the two chassis he tried today. “With the stiffer chassis I have some vibration, so I prefer the intermediate one that gives me a little bit more corner speed but without vibration,” he said.

Valentino Rossi said now he has chosen a direction with the chassis he would test his preferred option again in a test session immediately after the final round of the season in Valencia in early November.

“The lap time was not so bad but for me the chassis is a good way to follow. Already our bike is not bad in this area but it is a small step, but we have to improve the engine.”

Valentino Rossi said he had been told in advance there would be no engine upgrade for the test today, but he said he hoped to have the new 2008 prototype M1 motor in Valencia.

A lack of performance from the engine compared to the blistering top speed of Casey Stoner’s Ducati is the biggest area to improve for Yamaha engineers according to the seven-times world champion, who has now gone two successive years without winning a world title for the first time in his career.

He told MCN: “On the engine we have to work in two ways. We need a little bit more horsepower but with the same fuel consumption and secondly, and not less important, is the character of the engine from the bottom.

“At the moment it is a little bit too aggressive. For me as well the future will always be in the electronics as well, so the tactics to control the engine with the management system is what we need to do.”

Coming soon: Exclusive video footage of Rossi’s 2008 Yamaha.

For a full technical analysis of the new bike see the October 3 issue of MCN.