Valentino Rossi and Movistar Yamaha team-mate Maverick Vinales have welcomed the news that 2017 MotoGP podium finisher Jonas Folger is to become the factory's new European test rider.

Folger was forced to step away from full-time racing at the start of this year due to the fatigue problems that caused him to miss the tail end of last season.

However, the 25-year-old has recently been testing Moto2 machinery for Kalex and will now help steer development of the 2019 M1, with electronic-related acceleration the main area pinpointed for progress.

"I'm very happy about this decision," Rossi said. "I pushed a lot with Maio [team boss] for Folger, because for me Folger has a very good talent. But especially he is a young rider and not an ex-rider. This means that he can ride the M1 similar to me and Maverick, and he can make a good job, especially with the electronics, which is important for Yamaha."

"My opinion is that Jonas should race in the MotoGP World Championship, not test," said Vinales, echoing his previous view of the young German's talent. "But anyway for us it’s great to have Jonas because he’s really fast. He already has experience with the Yamaha. For us it’s good. He’s a good guy. I have a good feeling with him, so let’s see how we work together and hopefully we can build a good bike."

The pair were speaking after Friday practice in Misano, where Vinales was fourth fastest (+0.213s) and Rossi eighth (+0.588s) as Ducati riders Andrea Dovizioso and Jorge Lorenzo led the timesheets.

The Italian admitted it had been a 'difficult' day at his local circuit, being left only 15th after a problem with his second bike in FP1, before rising up the order after in the afternoon.

"It was for sure a difficult day because especially with the tyres we expected to work with the harder option. Because when we came here for the test the grip level of the track was higher," Rossi explained. 

"But for some reason, also with the rain yesterday, the track even if it's a bit colder is more slippery. So we have to work more on the soft and the medium tyres. 

"From some points of view I'm quite happy because I feel better with the bike compared to the test. We modified the setting and we improved. Especially in the fast part, now I'm not so bad. 

"But we had a lot of work to do because in braking I suffer. It's a bit difficult to stop. And also we have to work a lot on the electronics for find the right way to give the power. 

"The first target is to stay in the top ten already today, that is always very important and we are there. But if we want to make a good race we have work a lot and we have to improve our speed."

Rossi also revealed he is using some small electronic improvements, first used at Silverstone. It is "a bit better" but the Italian warned the work now being down by Yamaha Superbike electronic-ace Michele Gadda is "for the future".

"I think all the staff and Michele will work especially maybe for the future because at this moment we are more-or-less with the same stuff," he said.

While the forecast afternoon rain stayed away, Rossi warned that any overnight rain will reduce the grip level and hurt their chances. 

"Usually during the day the track improves and is better for our bike. But if it rains hard it is like you start from zero," he said. "So after yesterday's rain we start from zero. Looks like the forecast is quite bad for tomorrow morning.

"So I think Sunday will not be perfect conditions, but anyway is very important that Sunday will be dry because for example last year was a very bad day, a lot of water. So we hope it will be dry and we will try the maximum."

Speaking of rain, Rossi was asked for his response to the news that future MotoGP races will be rescheduled for a Monday or Tuesday if, as happened with the water-logged Silverstone asphalt, they cannot be held on a Sunday.

"I think we speak very much about Sunday, Monday or Tuesday. But the problem is the asphalt," Rossi replied. "So they have to do an asphalt that is good when it rains. We don’t have to race Monday or Tuesday. 

"For me it's something that you say to move the attention. But the problem is the asphalt was bad. It was not a problem of Sunday or Monday. Anyway, if you have to race Monday it’s okay. The important thing is we have time to go to the next race, so we can stay one week if they want!"