Valentino Rossi has made it clear to Yamaha that even though he and team-mate Maverick Vinales now agree on which spec of engine to use in MotoGP 2018, it's only enough for fourth place at best.

After a day's testing at Jerez, the nine-time world champion believes the step made by the M1 engineers is not big enough and top speed, at the Spanish track at least, is the same as it was last year.

"The way is quite clear for the engine choice. But from what I feel it doesn’t make a lot of difference. The problem is that for me we don’t make a big step. If you compare to the other top guys, more or less our speed is the same as this year," said Rossi, speaking at the track.

"For me the problem is this: With the new tyre, the bike is very good. Maverick is very fast. Also Franco, who doesn’t have a lot of experience, is always good. But if you check deeply, after four or five laps, for some reason we suffer more.

"So more or less, Yamaha have to be clear that it is not enough. For me, if we race tomorrow we are fifth, sixth, seventh. Maybe fourth if one crashed in front. But we don’t fight for the victory."

Rossi didn't take part in a session-end time attack as one of his new engines shit itself.