‘Grip balance behind Sepang problems’

Michelin claims that the various high-speed falls during the Sepang test on Thursday were caused by a difference in grip balance between the rubber used on the front and the rear tyres.

Various riders crashed out in high speed accidents at turns three and five in particular, including Jorge Lorenzo, Andrea Dovizioso, Aleix Espargaro and Jack Miller.

Thursday's test was the first official use of the Michelin prototype rubber, which is being developed for the 2016 season when the French company take over from Bridgestone as official supplier of rubber for MotoGP.

"What we are lacking now is a good balance front and rear. How the tyres work together. Front and rear balance is something you hear a lot about in car racing, but you also get it in bikes," Michelin Racing's technical director Nicolas Goubert said during the test at the Malaysian track.

"Basically the two accidents at Turn 3 for example were because riders opened [the throttle] probably a bit early. Maybe they wanted to take the most out of the rear grip and the front couldn't cope with opening so early.

"Some other riders, that didn't crash, said quite quickly that they couldn't use all the potential from the rear on the exit of the corner because the front is not at the right level yet."

He added that grip balance could be amended with different bike set-ups, but feels that it is impossible to make that sort of changes when trying to compare how different tyre compounds compare.

"For me it's not only a tyre issue and some manufacturers' said straight away that they could work on the setting of the bike as well. They cannot do that today because we don't have time," Goubert continued.

"So we said ok, for the future we will work on our side and with the test riders and they will work to adjust the set-up. We have a clear diction."

Michelin brought three different rear tyres and two different from ones to Malaysia and Goubert feels reliability and endurance aren't major issues after various riders, including reigning champions Marc Marquez, completed a race simulation with little effort.

Whilst official lap times weren't available, riders were timed in the 2m1s range, which is comparable to the average of 2m0.7s Marquez set on Bridgestones at the same track during an official test three days earlier.

No rider is thought to have broken the two-minute barrier, after Marquez posted a time of 1m 59.1s on the Bridgestones earlier.