MotoGP wunderkind Fabio Quartararo finally got his hands on the first spec of the Yamaha YZR-M1 2020 engine at Jerez and although fast says there is lots to do.

The Petronas SRT rider finished day one second on the timesheets behind Maverick Vinales - but three-quarters of a second adrift - with team-mate Franco Morbidelli another couple of tenths in arrears.

"We ran most of the day with this new engine. It was really difficult to understand because we make all the year with the same bike and then when you get a new engine you need to work on things like the electronics and that was mainly the plan of today," said the Frenchman, speaking at Jerez.

"Tomorrow will be the same, trying to get a better feeling and of course it's important that first of all we have a base. We are not exactly comfortable like with last year's bike yet. Now the pace is good, but I'm not as smooth as before.

"For us, it was the first time that we tried this new prototype engine and of course it's never easy to go fast when you have new things on the bike. It was more to understand."

Quartararo acknowledged the gap to Vinales was sizeable but said the Spaniard already had two days with the new engine at Valencia, so it was to be expected.

He already made two days of testing in Valencia with the new bike and we know Maverick is a really fast rider. We also never made one run really pushing for two laps like we do normally when we are on top of the screens.

"When I put the new tyre there was a red flag, so the tyre had already done two laps. Then you go out again and it was raining. Then the third time I went on track and made the lap time, but each time you go out-and-in the tyre drops.

"But we made a really good pace with old tyres, I think with 30 laps on the tyres I was one or two tenths from my fastest lap. I think this is really positive, also for our bike."