MADRID, Dec 2 - Dethroned MotoGP champion Valentino Rossi has said he is more determined than ever to reclaim the world title after testing on the new 800cc bikes for next season in Jerez.

After five consecutive years as MotoGP and 500cc champion the 27-year-old Italian lost out to American Nicky Hayden in a dramatic finale to last season in Valencia.

"It hurt a lot to lose but I am more motivated than ever, and feel stronger than if I had won," Rossi said in an interview with sports daily Marca on Saturday.

"To return to win the world title again after having won it five times is a massive incentive for me."

In 2007, bikes will be limited to an engine size of 800cc instead of the previous 990cc. Rossi said: "The new bikes don't have the brutal power of the 990cc but they ride really well because they are well balanced. They are great fun."

On the final day of testing, Honda rider Dani Pedrosa set the fastest lap time with Rossi second quickest on his Yamaha.