Maverick Vinales admits he feels 'lost' with the race day performances of his Movistar Yamaha, after seeing a front row start turn into eighth place in the Italian MotoGP.

As well as qualifying strongly, the Spaniard had set a fast pace in Saturday afternoon's final practice and was again competitive in morning warm-up.

But when the lights went out for the start of the 23-lap grand prix he lost 'over one-second' of pace, felt like he was being limited to 50% of his potential and barely broke a sweat due to the lack of front grip.

Consistency means that - despite just one podium this season - he is third in the world championship.

However Vinales warned Yamaha that the bike must improve, adding the factory "promised me a bike to win, not to be seventh and fighting with satellite Ducatis."

'I'm getting lost'

"Honestly for me it's so difficult," Vinales began. "I'm getting lost, I'm getting lost because I work in the practices in a good way and I think I'm competitive. And I don't know why from FP4 to the race we lose one second - or even more because in the last laps I was '49.5. Last year on the penultimate lap I did a '47.8.

"I honestly cannot believe the bike is worse like this. It's difficult to believe honestly as a rider. I cannot push. Honestly,I t's like I'm going at my 50 percent. I did not even sweat in the race because I cannot push. I can only do what the bike wants to do.

"During all the race I felt really bad. Honestly I felt I was crashing in every corner. Especially with the front. A lot of slides. Finally, I managed to go a little bit faster because I tried to reduce the speed in the corner, to not get this slide, and use a little bit more the rear.

"Luckily the rear was morning quite well compared to the opponents, but the front was horrible.

"I tried to get an explanation because as a rider you get lost, FP4 good feeling, qualifying incredible, warm-up really good. When I finish warm-up I say, 'Today I have the chance to win. I will go for it'. Then you arrive in the race and no feeling. It is difficult."

Listen to that noise! Bikes of MotoGP: Which sounds best? Video of Listen to that noise! Bikes of MotoGP: Which sounds best? CrashTV: Video Thumbnail:

'Yamaha promised me a bike to win'

Could it have been the hard-asymmetric front tyre that caused Vinales' difficulties?

The Spaniard doesn't think so, as the problem has occurred at almost every race since round six of last season, regardless of tyre spec.

"This morning I was quite fast with used tyres and then in the race everything was wrong," he said.

"It was completely the same bike, same electronics, we just changed the tyres and the bike was completely different. So I don't know, maybe after the Moto2 rubber or something, but I have no grip. Especially on the front.

"In the race, on the first lap I lost a lot of positions because in Arrabbiata 2 I lost the front. I don’t know how I didn't crash because normally didn't give you much warning, when it goes, it goes, but I was able to save and bring at least an eighth place home.

" I think the problem is to do with the tyres. The way maybe we warm the tyres or something. Anyway, last year in the first races I didn’t get this issue. And then every race since, sliding, sliding, no grip, no grip.

"I'm trying to find an explanation because [I'm only] 28 points behind, I want to win the championship. But I need the help a little bit of the team and when I signed with Yamaha it's because they promised me a bike to win.

"It's time to show that the bike can win.

"I hope Yamaha receive the message and start to work because they promised me a bike to win. Not to be seventh and fighting with satellite Ducatis."

No regrets about signing new contract

Despite his call for action from Yamaha, Vinales was quick to shut down any suggestions he regrets signing a two-year contract extension with Yamaha before this season had even begun.

"No. No. As you saw on Saturday, I was able to be in the front even without confidence. So when I get the confidence back I'm able to make poles, I'm able to make really good lap times.

"But the problem is in the race. The practices are good, but the races are bad.

"So it's really strange because when I was in Suzuki, the practices were normal and then in the race I make big steps always. And now it seems in the race I always go down a level.

"I'm lucky that my riding style is helping me a lot at the end of the race to recover, if not I'd be eleventh or twelfth. Let's see.

"As I said I'm here with Yamaha to win, at least they promised this. Let's see if from here until the end of the season we can improve and we win. We are 28 points behind Marc, there is still a chance. So I hope they push."

'The bike needs to improve'

"We need something new, because the bike needs to improve. But I don’t know. My problem is not that the bike is bad because in FP4 I was fifth, the warm-up I was fourth, in qualifying I was third. I only have problems in the race. That I have no grip from the tyres.

"If the bike worked normal I was able to be with Jorge, I think. Looking at the lap times I did later, with the bike that was not working very well. So let's see. I'm enthusiastic because I cannot push and I'm still there."

'Yamaha have two riders that can win the title'

Both Rossi and Vinales are also 'still there' in terms of the championship, holding second and third despite being yet to win a 2018 race.

"My best result was second in Austin, otherwise I'm fifth, seventh, seventh, seventh… and I'm still third in the championship, five points off Valentino and 28 from Marc," Vinales said.

"So even when things go bad the championship is not going away.

"So for me this means that we have to react and we have to find a solution now. Not more. It's one year already or more that we've had these problems. I know it's difficult and in the practices we've solved quite a lot, but in the race no.

"If Yamaha want, they have the chance to try to win the title. They have two riders that can win the title."

Rossi also stated he needs to start winning races and is currently 'not fast enough' to win the championship .

'Tyre grip the difference to Rossi'

With team-mate Rossi celebrating a podium finish on Sunday, Vinales was asked to explain the difference.

"I don’t know, honestly, because the bikes were quite close. Just the tyre grip was a big difference, from Valentino to my bike. Because riding similar I have better grip exiting the corners, as I'm a little bit more light, all the problems comes with the front tyre."

'I will forget the Catalunya test'

The next event will be Vinales' home round at Catalunya, where he was fastest at a recent private test on the resurfaced circuit.

But after so many disappointments, he's going there with a neutral mind.

"I will not be positive or negative, I will go there with a clear mind and try to build a good weekend. I will forget the test because at the test there was incredible grip and the bike was working incredible, honestly.

"…But in Jerez with new tarmac the bike was incredibly bad in the race. So I will forget and work again hard, hard, hard to try to be in the front and then we see."