Yamaha MotoGP riders Valentino Rossi and Jorge Lorenzo have played down rumours that they could race as team-mates against the likes of Casey Stoner and Michael van der Mark in this year's Suzuka 8 Hour endurance race.

"I hear this. First of all I would like so much to race together with Jorge. It would be very interesting and funny. Also to bring the new R1 to the race," said Rossi, winner of round one of the new MotoGP season.

"But sincerely - I don't know exactly the date of this year's 8 Hours, but I did it in the past, 2000 and 2001, and it was a great, great effort. You have to fly to Japan two or three times [for testing] and also the race is very hard. So I think for this year it is difficult but maybe in the future."

Lorenzo confirmed that he and Rossi have discussed racing together - and not just at Suzuka - but also thinks an entry in the 2015 event is unlikely.

"We speak sometimes with Vale to race in the future this race [Suzuka] or even a car race, like the 24 Hours of Le Mans as we are big fans of cars also," said the Spaniard, also speaking on Thursday at the Circuit of the Americas.

"But at this moment in our careers I think it is quite risky. To go over in the summer, the middle of the holidays, for an endurance race. Maybe in the future. For the moment Yamaha didn't say anything to us about that so I don't know."

This year's Suzuka 8 Hours, one of the most important events for the Japanese manufacturers, takes place on July 26 - in the middle of the MotoGP summer break. The event will mark double MotoGP world champion Stoner's first motorcycle race since retiring from grand prix at the end of 2012.

Rossi won the Suzuka 8 Hours with Colin Edwards in 2001.