Valentino Rossi has hit out at Bridgestone over its decision to bring its hardest-specification rear tyre to the Indianapolis Grand Prix this weekend.
The Ducati rider said that he had pleaded with the Japanese tyre manufacturer to choose a softer compound for the event as the newly resurfaced infield section of the track was likely to react better to such rubber.
"I already talked to Bridgestone in Mugello to modify the allocation for here because the rubber we have on the harder tyre is completely useless," the seven-time world champion said.
"But they don't modify it so we have to manage with just five or six tyres for the weekend."
Rossi said that while he believes Ducati has made significant progress with its GP11.1 since its debut at the Dutch TT in June, he is still suffering from a lack of front-end grip, which led to two off-track excursions during the afternoon session.
The Italian wound up sixth during the morning session before dropping to 11th later on once more rubber had been put down on the track surface.
"We made a mistake and didn't make a good setting," he added. "We had to follow the condition of the track as it improved. At least [team-mate] Nicky [Hayden] looks okay. We have to take a more normal set-up tomorrow.
"So I didn't have grip on the front at all. Braking and corner entry is very slow. Tomorrow we will modify [it]."
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