Marlboro Ducati's Valentino Rossi has admitted there is more work to do to fix the front-end grip problems he has suffered with all year but using the new aluminium perimeter frame makes developing solutions much easier and faster to implement.

The nine-time world champion rode an experimental version of the GP12 today at Valencia and said that although there is a more positive feeling with the bike, his corner speed problem, or lack of it, is still there and he also has too much wheelspin under power.

"Today is not so bad in the sense that the feeling with the bike is good, the 1000cc is better to ride compared to the 800cc and the feeling is positive. It is the first time we try this configuration so we need some experience and some more data for understand. Unfortunately some big problem remain so we arrive to one level but we are not able to improve during the afternoon," said The Doctor, speaking to bikesportnews.com this evening.

"Our problem is always in the centre of the corner and I don't have enough grip from the front to carry enough speed. We expect this remain as we think it is another type of problem and there is a different way to fix. Also, we are struggling with acceleration because with this amount of horsepower we wheelspin too much. We have to modify some weight distribution and electronics.

"We expect the problem is not in the material (of the frame). We expect we have to work more on the bike to fix. With this frame and this configuration we can work on the bike a lot better in the sense that for make some modify we need less time and especially with the six-engine rule, if we need to make some more modify we don't have to change the engine so it is more easy to try and make development.

"We have worked on the riding position because I still don't feel comfortable and we modify some things and all is improve but we need to do some other steps. I feel more confident on the bike."