Yamaha in a dilemma over 2008 line-up

Although the team are keen on grooming a young star to become number one when Rossi eventually retires, team boss Davide Brivio admits that there seems little reason to bring an end to the excellent working relationship the Italian rider enjoys with current teammate Colin Edwards.

The American's contract with the team runs out at the end of this year, and there has been speculation that 250cc championship leader Jorge Lorenzo could be promoted to MotoGP with the Fiat Yamaha outfit.

But Brivio has made it clear that they have not settled on their rider strategy decision yet.

"We decided that we wanted to remain with the current team last year," he told Motor Cycle News. "With Colin we have started a very good relationship in 2005 and 2006. It is always a dilemma. The dilemma is always whether you start working with a new generation rider or to continue with the existing riders.

"In this moment I have to say that our team and our rider combination and atmosphere is the best I ever had in my career. During the winter Valentino and Colin worked very closely on developing the new bike.

"I would say there is an almost unique relationship between them. It is rare and not often seen in racing that there is this type of relationship. For us this is a big asset.

"Sooner or later we have to start to think about the future but in this moment we are working on the present. There is no doubt that Casey has a great talent but we knew this before. We didn't need to wait and see his results now to know that."

Brivio believes that all the sport's manufacturers are looking at younger riders who could become the big stars of the future.

"What Yamaha are thinking about for the future is no different to Honda and Ducati. Many good riders are coming from 250s," he explained.

"Casey and Dani Pedrosa were the good guys to come first and now we wait for the new generation like Jorge Lorenzo and Andrea Dovizioso. We are looking at the market right now.

"In 2008 and 2009 though I'd expect there will be eight or nine very strong young riders, because Casey and Dani will still be very young, and Nicky Hayden, Marco Melandri, Toni Elias not much older.

"Everybody is looking for the next best one and Yamaha, Honda and Ducati all want a card to play."