Marlboro Ducati's Nicky Hayden is still unsure whether he should race the new GP11.1 at this weekend't Laguna Seca MotoGP round as it may end up costing him a precious engine from his already depleted allocation of six to last to the end of the year.

He had hoped to ride the bike at the Sachsenring but a shortage of parts meant only team-mate Valentino Rossi did that. Hayden beat the nine-time world champion but says Laguna Seca is now getting bumpy and isn't an ideal place to be doing back-to-back tests.

"We're going to send both bikes and we might try one of the new ones because we're not really getting anywhere. At the the end of the day, Vale and I are basically the same, I don't think there is a whole lot of difference but he definitely feels there is more potential with the new one and so do the engineers. The sooner we get going on it the better it will be for the end of the year and the start of next," said the American.

"We will send them but I don't know which one to ride. The only way to be clear is to go with two of each, not one of each so we can do a back-to-back test. Laguna is not an easy track to be testing bikes though but is a track I love. The gap to the front is a lot, I got beat in Germany by 27 seconds and I was riding hard. Pushing hard to get beaten by that much definitely stings."

"We can try both on Friday and for Saturday have two the same but the problem is if I leave the pits on the new one and I don't like it I have used another engine. We have got a lot of stuff going against us and it's not an ideal situation."