Valentino Rossi's front tyre at the Chinese GP

The results of Michelin's analysis
On lap 16 of last month's Shanghai GP, Valentino Rossi had to pit due to excessive vibration from his front tyre, which was found to have been caused by the loss of a small piece of tread.
The tyre remained inflated despite the missing piece of tread.

The analyses conducted at Michelin's Clermont-Ferrand HQ did not show any fault in the tyre. The same tyre specification was used by seven other Michelin riders in the same race without any trouble throughout the 22 laps.

The very high level of stress experienced at Shanghai by the centre part of the tyre is the highest during the whole MotoGP season, because of frequent decelerations from over 320km/h to 60km/h within less than eight seconds.

It would appear that this tyre could not sustain that level of strain; the safety margin we always include when we develop a tyre was apparently not enough in this particular case.

The parameters that influence the levels of stress that a tyre undergoes are, among others: track layout, grip level, riding style and bike set-up.


We apologise wholeheartedly to Valentino and the Yamaha team for having failed in this case to provide a front tyre capable of being competitive throughout the race.

We have, of course, already taken all necessary measures, where physically possible, to ensure that such an event doesn't happen again.