The main aim for Yamaha Motor Racing managing director Lin Jarvis is to keep all four of the present YZR-M1 MotoGP riders - Valentino Rossi, Jorge Lorenzo, Colin Edwards and Ben Spies - for 2011, but he expects Honda to be 'aggressive' in its rider recruitment.

"The ideal scenario for me at the moment would be honestly speaking to retain all four," said Jarvis, during an interview with David Emmett of MotoMatters.com. "That would be the perfect scenario."

Yamaha has gone from claiming just one podium during the 2003 season to winning four of the six MotoGP titles since 2004, when Rossi arrived from Honda, and finished one-two in last year's championship with Rossi and rising star Lorenzo.

Rossi (20 wins), Lorenzo (6 wins), Ducati's Casey Stoner (20 wins) and Honda's Dani Pedrosa (6 wins) have won all but three races since the 800cc era began in 2007, but have also remained remarkably loyal to the respective employers.

Rossi has been with Yamaha since 2004 and Lorenzo since his MotoGP debut in 2008. Stoner won the title during his first season with Ducati in 2007, while Pedrosa has been a Honda rider ever since the start of his grand prix career - and at Repsol Honda since his MotoGP debut in 2006.

But various tensions seem to be simmering under the surface for all four riders - all of whom are out of contract at the end of this year.

Whilst Jarvis wants to keep his existing line-up, he admits retaining both Rossi and Lorenzo in the factory team will be a challenging task, especially in the face of an 'aggressive' Honda, desperate to regain its former glory.

"In a way, our problem [with Lorenzo and Rossi] that we have now has been created by, I would like to say good planning, because nobody knew when Valentino may or may not stop," Jarvis explained.

"And so we recruited Jorge early, in order to bring him on and bring him up to speed so that if eventually Vale decided to retire or go to cars or Formula One or rally or whatever, we would have a succession scenario.

"Now we have a situation where Valentino is riding as good if not better than ever; he's still motivated and wants to stay in the sport, and Jorge has done pretty much what we expected of him, so they're pretty much, often on an even par.

"So it's not going to be easy to keep them both in our project - we would like that, but let's see, because I'm very much a realist.

"I personally think something's got to happen in Honda; they will make a move sooner, rather than later I believe. And depending on what they will do, well, there's only a very limited number of super top riders at the moment.

"Ben is already on a contract with us so you can rule out Ben, so you've got Vale, Jorge, Casey and Dani. I think Honda will be quite aggressive in their rider recruitment, and let's see which rider they will approach.

"I think both for Vale and Jorge, we'd like to keep them here, and I think they're both very happy here. I still believe for next year this will be the best place for both of them, but... nobody knows what will happen."

Rossi, who quickly disowned comments in a BBC interview (late last year) that Yamaha would have to chose between him and Lorenzo for 2011, could make some kind of announcement about his future during his home Italian Grand Prix from June 4-6.

Meanwhile, rumours are already circulating that Honda has agreed a deal with Stoner, something both Honda and Ducati deny.