Rossi reckons Spies will need time

Spies will join Tech 3 Yamaha next season after just one year of World Superbikes. The four times AMA Superbike champion took three victories in his first four races in WSB and is just three points behind championship leader Noriyuki Haga with four rounds left.

But Rossi reckons Spies will be hard-pressed to impress that much in his MotoGP rookie season.

"I think Spies has the potential, but for sure he needs time to understand the bike and the tyres, and to demonstrate that he's a top MotoGP rider," said Rossi.

"For me, the MotoGP riding style is very close to a 250cc riding style now. Riders especially like Jorge [Lorenzo], but also like Dani [Pedrosa], [Casey] Stoner, and maybe [Marco] Simoncelli next year, arriving from 250cc have a big advantage compared to the riders that arrive from World Superbike.

"The style of riding these bikes, especially with the Bridgestone tyres, is more similar to the 250s, and has a big difference compared to the Superbike.

"Together with this, the 250cc riders know all the tracks, and the World Superbike riders know just two or three. So I think it's a lot more difficult for Superbike riders to arrive at the top in MotoGP, especially in the beginning, compared to riders from 250cc.

"But maybe it's just a question of time, because Ben is young. I think he's the only guy in Superbikes at the moment who is able to win in MotoGP."

Rossi backed Spies' decision to move straight into MotoGP next year, having previously signed a deal to graduate in 2011.

"I think it's the right decision to come straight away," he said. "He's quite young, and can have one extra year for experience and trying to understand the MotoGP bike. He will be another great rival for next season."

He also believes Spies' arrival strengthens MotoGP's position compared to World Superbikes.

"I think it's very good for Yamaha in the future, and I think it's good for MotoGP, because there are not a lot of us, but for sure the quality is very high," said the current MotoGP champion.

"The numbers are not fantastic, but with Ben all the best motorcycle riders in the world will race in MotoGP, so it will be more interesting."