The second of two races taking place on American soil this season will be held this Sunday at one of the most revered motorsport venues in the world, the legendary Indianapolis Motor Speedway, whose distinctive layout places significant demands on Bridgestone MotoGP™ tires.
The Indianapolis circuit comprises three distinct parts; the renowned oval which forms the main straight, the opening complex and turns seven and eight built specifically for MotoGP™, and the rest of the infield which was constructed for when the circuit held Formula One races. Large sections of the circuit were resurfaced last year, resulting in more consistent grip levels, while some undulations on the tarmac that caused the bikes to behave erratically in corners were also removed.
After revising its tire severity ratings for each circuit, Bridgestone will now supply special construction asymmetric rear slick tires in the medium and hard compounds at Indianapolis to manage the very high tire temperatures the 1000cc MotoGP™ machines are expected to generate around this circuit.
The circuit’s abrasive tarmac and counter-clockwise layout with its fast and frequent left handlers makes it one of the hardest events of the season for the left shoulder of the rear tires; hence asymmetric rear tires with considerably harder rubber on the left shoulders are supplied.
The abrasive Indy track also means the extra-hard compound front slick is included in the tire allocation alongside the soft and medium compounds.
Bridgestone slick compounds available: Front: Soft, Medium, Extra-hard. Rear: Medium, Hard
Bridgestone wet tire compounds available: Hard (Main), Soft (Alternative)
Hiroshi Yamada - Manager, Bridgestone Motorsport Department
“It is always a pleasure to visit Indianapolis as the motorsport culture here is very strong and the whole city gets behind the Grand Prix with many events taking place over the weekend. The venue itself is quite unique with elements of three different eras incorporated into the circuit and it is a challenge for both riders and tires. Perhaps due to its particular layout, Indy is a race where the result is always hard to predict with four different winners and seven different riders making the podium since the race was included on the calendar four years ago.
Apart from the regular MotoGP roster there will be two extra riders in action at Indy. Steve Rapp will once again be riding the Attack Performance-Kawasaki CRT entry, while Aaron Yates will debut the GPTech-Suzuki CRT machine so I expect even greater interest in this race from the American fans this weekend. To give these wildcard riders the best possible preparation for the coming weekend, our race engineers were on hand to assist both teams in a test at the Indianapolis circuit that took place on Saturday.”
Shinji Aoki - Manager, Bridgestone Motorsport Tyre Development Department
“Indianapolis is split into three sections; the sectors from turns one to four and turns seven and eight were designed for MotoGP, the rest of the infield is part of the old F1 circuit, while the main straight is part of the world-famous oval course. This causes the character of the circuit to vary in each section, though a resurfacing last year has made the grip levels more consistent across the whole course. The circuit’s layout causes very high tire temperatures through the high-speed left-hand corners, so asymmetric rear slicks with much harder rubber on the left shoulder are required here to provide the necessary durability and grip for the race distance, while ensuring good warm-up and grip characteristics on the lesser used right shoulder of the rear tire.
This year we have revised our rear tire compounds for Indy and have gone one step softer with both options, with the medium and hard asymmetric rear slicks being supplied. Additionally, the rear slicks for this circuit now feature the same special heat-resistant construction as those provided at Mugello, Sachsenring and Phillip Island. Our compound selection for the front slick tires also changes this year, with the soft, medium and extra-hard options now being made available to provide riders with a front tire option for every kind of track condition.”
Source: Bridgestone MotoGP