Rossi, Jarvis: Yamaha problems stem from 2016

Yamaha's difficulties with its MotoGP machine stem from changes made after the 2016 season and, now the problems have finally been identified, the factory is trying to play catch-up against Ducati and Honda.

That's the opinion of Movistar Yamaha team principal Lin Jarvis and also Valentino Rossi, speaking on Friday at the Valencia Grand Prix.

Yamaha suffered its longest ever MotoGP win drought, stretching from Rossi's 2017 Assen victory until Maverick Vinales' win at Phillip Island last month, with engine and electronic changes now in the pipeline to make the M1 a regular frontrunner in 2019.

"I would say there was no single mistake, I think not getting to grips to truly understand the problem two years ago was the mistake," said Jarvis.

"So everything that happened this season was a consequence of not taking the right decisions in the past. In the middle of this season I think, finally, it became very clear what we had to do.

"But now we have to catch-up and we are behind our competitors, in particular considerably behind Ducati I think and also Honda."

Rossi said he agreed with that assessment.

"For me, at the end of 2016 we had some problems, we were strong but we suffered already with the tyres and it looks like also the other manufacturers in that moment made some big steps.

"But unfortunately we tried to fix this problem not with the right stuff.

"We tried to work on the chassis, on the weight distribution, when for me we had to work more in other areas like the electronic and engine. So yeah, I agree [with Jarvis]."

While some electronics updates have already made their way to the race team, engine design changes cannot be introduced during the grand prix season.

Rossi and Vinales will test a 2019 engine at next week's official test.

"We will have something to try during the test. Especially a different spec of engine, the 2019 version," Rossi confirmed.

"We hope that it can have good power but at the same time we need more smooth [delivery]. So this is what we expect."

The Italian was speaking after setting the twelfth fastest lap time during a wet opening day in Spain.

Rossi recorded his fastest lap during the morning session, but rose to third on the timesheets in the slower afternoon session.

"It was an interesting day because it was a day of full wet, so we could work a bit on the balance of the bike, also because during this season we don’t fortunately have a lot of water," he said.

"This morning the track conditions were faster, with less water and the lap time is quite impressive because it's just 7-8s slower than the dry. So very fast. But this morning unfortunately I didn't make a very good lap and I didn't feel good with the bike so I was not in the top ten.

"But for the afternoon we improve the setting of the bike, the balance and in the afternoon I felt good. I was quite strong in the pace and this is important. The shame is that with more water we are not able to improve the lap time of the morning, so I'm not in the top ten.

"Tomorrow FP3 will be crucial to try to stay in the top ten and now we have to wait also to see which conditions because it looks like tomorrow the weather will be better. So we hope to be ready for the dry conditions, if it will be dry, to try to stay in the top ten and after we see.

"For Sunday, looks the weather is like today so we have to be ready for the wet. Naturally we will try to work on all the small details and especially make the right tyre choice."

Rossi admitted the M1 had been a 'nightmare' in the wet at times last year, but that this year's (2016-based) chassis and the recent electronic work have improved the situation.

"Last year was a very bad feeling, it was a nightmare because the 2017 bike was very difficult to ride in the wet," he said. "We and Yamaha worked and the 2018 bike is more like the old Yamaha that in the 2015-2016 we were quite strong in the wet.

"That is one thing. The other is that we worked on the electronics, which are very important in the wet. We tried to make the bike smoother and easy to ride and it looks like also in the wet we are not so bad."

Red flags appeared during both of today's MotoGP sessions, due to track conditions, with large amounts of standing water on parts of the track.

"For me, everything depends on the amount of water, because the track worked well. The asphalt has good grip in the wet and also good drainage," Rossi said.

"The problem is if it rains like this morning at 10 o'clock, you cannot race, because there is too much water and these big bikes make a lot of spray so if you are in a group you cannot see.

"This morning it was enough to wait 10-15mins and then the track conditions were better, so we have to do like this for the rest of the weekend."

Vinales, just two points behind Rossi in the battle for third in the world championship, was seventh fastest on Friday.