According to Eddie Lawson: Yamaha YZR-M1 Best Bike in MotoGP

This is sort of a no-brainer; Eddie Lawson claims that the Yamaha MotoGP motorcycle is the best in that series. It would not be tough for an outsider to come to the same conclusion after watching Rossi and Lorenzo battle it out for the lead in just about every race now. He does not believe it is the fastest, just the best handling bike in the class.

http://tinyurl.com/pvanrr