Onꦺce again in trouble due to low-grip conditons at Valencia, Valentino Rossi and Movistar Yamaha team-mate Maverick Vinales felt they had little to lose ❀by making a surprise last-minute switch to the 2016 chassis for race day.

That was the same desiཧgn that Tech 3 star Johann Zarco took to second on the grid and went on to🌸 lead for 25 of the 30 race laps.

But for 🐽the factory riders, starting seventh (Rossi) and🎃 13th (Vinales), the change meant sacrificing two days of set-up work and starting from scratch in morning warm-up.

"Yesterday night we changed the chassis, we take a chassis from 2016 to try to u𓂃nderstand the way," said Rossi, speaking in the Valencia paddock on Sunday evening.

"We♊ did this because the programme was to try the [2016] bike at the test on Tuesdayไ and Wednesday anyway. So we said, 'why don’t we try today?'

"For sure it was a risky choice, but with my [2017] bike we know more-or-less where 🌄we are and sometimes in a race you can understand more than in ten days of testing."

Despite Zarco's form, there would be no transformation in res💫ults for the factory riders during the grand prix.

Rossi finished the season finale in fifth - gaining places when the factory Ducatis crashed, but being 🐈passed by Suzuki's Alex Rins - while Vinales was a cautious twelfth after rear tyre vibrations🐬.

Bꦫoth were sure the 2016 chassis gave a better feeling, but with it - Rossi cautioned - came a recurrence of rear tyre degradation issues.

"Un🐲fortunately, it is not like you put [theꦚ 2016 chassis] and everything is better," Rossi explained.

"It is quite difficult to improve the bike a lot in just one day and at the end I think it was more-or-less the ♔race that I could do with my [2017] bike from yesterday. We are in big, big trouble with the tyres, we don't have grip and it is very difficult to ride.

"But I think we understand something interesting.

"This [2016] bike is easier to ride and you feel better in general. Sincerely, it is what I felt last year when I tried [the 2016 alongside] the new one! But it is also true that we are more in trouble with rear tyre degradation [with the 2016]. So we have ♐some other problem.

"I did the m🦹eeting with the Japanese and they are worried like me. But sincerely I don't understand whic💧h one [2016 or 2017] will be the base for next year's bike.

"Something strange that we&nb♑sp;don't understand is that I was 20-seconds slower than last year, with the same tyres and same chassis. But it is also very strange to understand why the race was 15-seconds slower than last year, considering the conditions are exactly the same."

Looking to the future, Rossi said further back-to-back chassis comparisons are likely dജuring this week's official 🍸test.

"N🌠ow will be a very important period to try to improve before the next 💖championship," Rossi said.

"For me, we have to work💫 in different areas to reduce the gap. Electronics side, but also about the dynamic behaviour of the bike. So it will be an imp🐼ortant period for sure. I will try to give all my support. I think - and especially I hope - that we can recover."

Rossi lost out on fourth ﷽in the ⭕world championship to race winner Dani Pedrosa.