Marlboro Ducati's Valentino Rossi is committed to developing the carbon fibre chassis on his Desmosedici MotoGP bike and says there is no way he would want to swap back to an aluminium beam frame that Japanese manufacturers use.

The Doctor's target is to reach the same feeling with Alan Jenkins' design which basically uses the engine as a stressed member with a carbon swingarm attached to it and the shock. There is a new rear end on the 2012 bike, which Rossi loves, but it can't be transferred over.

"We have a chance to fix the bike without using the normal style like the Japanese. I don't want an aluminium chassis, no way. Our target is to reach the same feeling as the Deltabox with this type of bike," said Rossi, speaking at the Silverstone round.

"Already the 1000's rear is a different design but we cannot put it on the current bike, we try to create the same effect with the current bike which is more stability and better load at the front. We will not try a new front this year I don't think."

Rossi has also had to cope with two other factors this year: new Bridgestone tyres and the fact that, after having half of last year off, he is not at physically fit as he is used to being.

"I also need to modify my style for these tyres because during the last year the riding style of the top guys develop a lot. The spec tyre have less grip on the edge so you have to set the bike and try to use it in another way - less on the edge and I lose all last year my fitness so I am a little bit behind this type of riding."