MotoGP star Valentino Rossi gave a 'colourful' description of his surprise at Bridgestone's decision to go ahead and change the rear tyre specification.

Both the 2013 and 2014 specification rears had been evaluated during the first Sepang test earlier this month, after which it was decided that only the 2014 tyres will be made available.

"The general consensus is that our 2014 specification tyres are working well," Bridgestone's Shinji Aoki had commented. "However, there is still a lot of work to do to help the teams get the most out of our new generation of tyres before the season starts."

Following the opening day of this week's return Sepang visit Rossi, Yamaha team-mate Jorge Lorenzo and Ducati's Andrea Dovizioso were among those who spoke of a general lack of grip - especially edge grip - with the 2014 tyres, something Rossi suspects is due to a stiffer construction.

Rossi, who set the seventh fastest lap time, explained: "The big issue for us at this test is to try and adapt the M1 to the new tyres, because in the first test we had some problems with the 2014 tyres.

"Especially with the soft tyre. But the situation is like this. They have already decided [to change the tyres] so we have to adapt the bike.

"Today we worked a lot on the soft and it was already better - not very good like the tyre of last year, but not so bad."

Asked by Crash.net if he had been surprised by the decision to change to the 2014 tyres, given the issues he and some others reported at the first test, Rossi replied:

"Yes. As always... Something happened that we cannot understand [laughs]. We just understand when it is already done. So when you are already f**ked! And it is very bad when you are f**ked and you don't feel nothing before - it is a bad surprise [laughs]! But anyway it is like this."

Lorenzo - who was fifth fastest on Wednesday - may have used tamer language, but the former world champion appeared even more disappointed than his team-mate.

"We don't find any solution for the [2014] tyres that Bridgestone gave to all the riders. It seems that for Yamaha it is much worse and they don't want to provide other tyres," he said.

"At the moment we are trying everything - all the set-ups we can - but the feeling is always the same on the track."

The Spaniard added: "We are trying to speak to Bridgestone to make them change the tyre, but at the moment they have a very closed mind about that and they don't want to change. They think this tyre is safer. For me it is the opposite. It is more dangerous."

Despite his dislike of the new tyres, Rossi believes he had the pace to claim a top three place on the Wednesday timesheets, having finished just half a second behind surprise leader Alvaro Bautista (Honda Gresini).

"At the end I am down in the ranking because I didn't put in the soft tyre at the end, because we were concentrating with the hard tyre to do a long run - ten laps - because of the problems at the last test.

"I am seventh, but if I used the soft I think I could have done a 2m 0s, so inside the first three.

"Also with the rhythm, I was constant. I did some good lap times. I am quite happy, but we have to go fast. Especially for Marquez."

Repsol Honda's reigning champion Marc Marquez, who dominated testing earlier this month, is missing this week's outing after fracturing his leg in a training accident last week.