Valentino Rossi says he is still suffering under acceleration as changes to the set-up of his Yamaha's electronics failed to yield the desired results on day two of MotoGP testing in Thailand.
The Italian admitted after Friday's running at the Buriram Circuit that his YZR-M1 was not accelerating out of the track's numerous low-gear corners, pinning the blame firmly on the bike's electronics.
Trying several set-up changes on the electronics, Rossi – who feels Yamaha has struggled to adapt to MotoGP's unified ECU software since its introduction in 2016 – ended the day 14th and almost a second adrift of Marc Marquez's fastest lap as his woes continue.
He said: “It was a tough day. We started quite well in the morning, and I did some good laptimes. After we had some work to do and something to try, and sincerely I didn't like it a lot.
“We tried some things with the electronics and with the settings, but unfortunately we don't find an improvement. We also had some work to do for Michelin.
“It was a tough day. Now we have to concentrate and speak with the guys to try and follow another way.
“We lose in acceleration a lot because we lose with the electronics, and the other manufacturers it looks like they're able to be faster and find something else.
“We worked a lot on that today but we didn't find the positive.”
Team-mate Maverick Vinales was left baffled by a lack of bike balance and edge grip for much of Friday and Saturday's running.
He too worked on the settings of the his M1's electronics in a bid to extract a slightly more aggressive power delivery from the engine, and was able to jump up to fourth from outside of the top 10 in the closing stages.
“It took a long time to understand which way to go on the bike, maybe too long,” said the Spaniard.
“I didn't feel good on the bike until the afternoon, feeling like I could ride with good pace, but we've changed some things and maybe that's the way to follow and we'll confirm it tomorrow.
“Following my feelings, my own set-up, that's when I feel good and I can ride with my style.”
