Maverick Vinales has produced his customary act of topping the timesheet during a MotoGP test as the final track action of 2019 began at Jerez with the Monster Energy Yamaha rider running back-to-back stints to compare both a new engine specification and new chassis.

The Spanish rider produced a late 1m 37.131s when conditions were at their best after early morning rain to set the fastest time on the opening day of the Jerez MotoGP test as he completed 68 laps in total.

Vinales focused his efforts on comparing his 2019-specification Yamaha to a new engine and new chassis and has been left content with Yamaha’s efforts to extract greater horsepower and top speed without risking its strengthens in the corners.

Having been left pleasantly surprised by the familiar feeling Yamaha’s new engine, Vinales pointed towards its new chassis as the biggest area of attention the Iwata factory needs over the winter before first pre-season test in 2020.

“The feeling is very similar. That is the good point, that the feeling is already straightaway very similar,” Vinales said. “For sure the other one [2019 bike] is after one full year and I have really good potential on that bike so we need to understand what is the good points of the new one.

“I think we need to improve the chassis but it is just the first prototype of the new chassis so for sure at Malaysia we are going to have more steps on the chassis.”

While Vinales has been encouraged by Yamaha’s efforts, he has dismissed the carbon swingarm which the factory began experimenting with midway through the 2019 campaign. After numerous trials with the carbon swingarm the Spanish rider ditched it to stick with an aluminium version – something he will continue to do heading into 2020.

“The carbon swingarm I tried two or three times in some FP1s and for me it was already worse than the normal one I have so there is no meaning to try it now,” he said.

“In Aragon with the standard bike I needed just six laps and then race so that was wrong. I did too many laps on the carbon swingarm and double exhaust. For me it is very easy and clear to understand if it works or not.”

Vinales led Petronas Yamaha’s Fabio Quartararo, who also tried out the new engine, with his team-mate Franco Morbidelli in fifth place on day one of the Jerez test. Valentino Rossi completed 64 laps but was only 14th fastest.