Yamaha concerned by power deficit

Although Yamaha started the 2010 season with a one-two in Qatar for Valentino Rossi and Jorge Lorenzo, the M1 appeared to lack straightline performance compared to its rivals - with Honda in particular seeming to enjoy a power advantage.

With each rider only allowed to use six engines during the 2010 campaign, Brivio is concerned that catching up could be difficult.

"We struggle on the straights," Brivio admitted to Gazzetta dello Sport. "Let's hope we can quickly find some small solution to patch the situation.

"But because of the new rule that forces us to use no more than six engines for the season, finding an immediate solution may be a bit of a problem. We must take into consideration the available units."

Rossi's bike stopped just after the chequered flag on Sunday night, having run out of fuel. Brivio confirmed Rossi's suspicion that this was simply because excessive wheelspin during the race had used more fuel, but said it had not been a drama and Yamaha's in-built automatic fuel management system had not been required.

"If the bike slides, you lose grip and the bike consumes more fuel," he said.

"We have a system that calculates fuel consumption during the race and leaves you with a sufficient amount to reach the end of the race. If it calculates that it's consuming too much, it steps in by reducing the power.

"There are tracks more problematic than others, and it has occurred in the past that we finished right on the limit. It also depends on the combination between track and temperature: when it's cold you consume more, less so when it's hot.

"During the post-race meeting we have established that the system did not step in. The fuel was sufficient, and in fact Valentino crossed the finish line with no problems. The system did not reduce the power."