Despite the gains made by Honda since the end of 2010, MotoGP world champion Jorge Lorenzo insists he 'can't imagine' leaving Yamaha.

After a winter spent warning about the relative progress made by the RCV, which dominated pre-season testing, it is nevertheless Lorenzo and Yamaha that lead the 2011 world championship after two rounds.

That's due in large part to Lorenzo wringing every single ounce of performance out of his M1 - and staying wheel-perfect while accidents, a lack of fitness and bad luck have taken their toll on his key rivals.

But the warning signs are clear: Lorenzo's second place at Qatar made him the only non-Honda rider in the top five, and he was the only Yamaha rider in the top seven in the wet of Jerez, where he won his first race of the season after a chaotic race.

"In the past few years, Yamaha has proved to be among the top MotoGP teams and now it is time to work stronger to keep our privileged position," said Lorenzo, during an interview with the official Yamaha Indonesia website.

Lorenzo has inherited the unofficial role of Factory Yamaha team leader following Valentino Rossi's move to Ducati and - like new team-mate Ben Spies - he has been calling for greater engine performance to take on the Hondas.

However the M1's handling characteristics remain strong and Lorenzo, who already has a Yamaha contract in his pocket for 2012, has no desire to start looking for employment elsewhere.

"My bike is very good, I feel very comfortable on it," he declared. "This is my fourth season in Yamaha and I can't imagine racing for a different team.

"This year, for the first time, I will also be developing the bike and it is a different challenge for me."

Bike development may be the most practical change for Lorenzo in 2011, but how does being the world champion alter things mentally?

"I don't think about myself as 'Jorge, the reigning world champion'. I believe in myself, I work hard to be on the top and that's all," he said.

"All riders begin the championship with zero points, your mental condition is very important to avoid a lot of pressure."

Lorenzo's mental condition couldn't be faulted at the first two rounds, leading to his debut win with the #1 plate at his most special circuit.

"Jerez is the track where I started my career, for me it is the best track in the world, I can not imagine MotoGP without Jerez," he said of the Spanish Grand Prix venue.

"It's the special one. MotoGP without Jerez would be like tennis without Wimbledon, F1 without Monaco or basketball without the Madison Square Garden.

"MotoGP needs circuits like Jerez and Assen."

In terms of new tracks, MotoGP has just confirmed that Texas will join the MotoGP calendar from 2013, while countries such as Abu Dhabi and India are also waiting in the wings.

Indonesia - despite being one of the most important markets for motorcycle sales - hasn't hosted a grand prix since 1997 at the Sentul Circuit. Lorenzo, a somewhat frequent visitor to the country as part of Yamaha's PR efforts, would like that to change.

"Indonesia is a country I love and the passion for MotoGP there is incredible," he said. "I would like Jakarta to join the MotoGP calendar soon, they deserve it. I've been five times in Indonesia and I hope to come back soon."

Of more immediate concern is round three of the 2011 championship, the Portuguese Grand Prix at Estoril - where Lorenzo has never been beaten as a MotoGP rider!

"I am ready to ride again in Portugal. Estoril has also become a special track for me in MotoGP. I won three times and I can do four in a row. But my aim is remaining on podium."

Free practice at Estoril takes place at the end of this month.