Round 17 and the penultimate round of the 2012 MotoGP season takes place at Australia’s Phillip Island circuit, where the picturesque setting of the track belies its status as one of the cruellest on Bridgestone MotoGP tires.
At roughly 4.44 kilometres in length, the majority of the Phillip Island circuit does not impose significant load on tires, but the final section through the left-handed turns 11 and 12 are taken at high lean angles under continuous throttle opening, resulting in wheelspin and the generation of extreme temperatures. In fact, Phillip Island’s last corner creates the highest tire temperature recorded during the entire MotoGP season.
This large variation in operating conditions over the course of a lap make asymmetric rear tyres a necessity at this windswept circuit. The left side of the rear slicks feature rubber that is much harder than the right shoulder, and the rear slicks also employ a special heat-resistant construction – like that used at Sachsenring and Indianapolis – to keep tire temperatures in check.
The front tire compounds for Phillip Island are the soft and medium compounds which offer the best combination of cornering stability and warm-up performance at a circuit that is renowned for highly variable weather. Phillip Island’s vulnerability to very cool temperatures also means that the main wet tyre for the Australian Grand Prix will be the soft compound option.
Hiroshi Yamada (Manager, Bridgestone Motorsport Department) says: “Phillip Island is one of the most impressive circuits on the calendar with its fast speeds and spectacular seaside location. This year’s Australian Grand Prix will be a particularly special occasion as it marks Casey’s last home race and although he already boasts an impressive record at the Island, undoubtedly he will give everything he can to score his sixth straight victory at the circuit in front of what will be a large home crowd.
“The championship battle is continuing right to the end and the three way battle between Casey, Dani and Jorge this weekend should make for exciting racing. Also, it is a shame that Ben’s injuries means he can’t ride this weekend, I wish him a speedy recovery and hope to see him back on his bike at Valencia.”
Shinji Aoki (Manager, Bridgestone Motorsport Tyre Development Department) says: “Phillip Island is a circuit with a very high average speed, however for the most part it is not demanding on the front and rear tyres because of the generally low temperatures encountered and flowing nature of the track.
“The last section of the circuit, culminating in the high speed last corner creates the highest rear iyre temperature of the season in the left shoulder and it is this characteristic that is the main consideration when developing tyres for this circuit. It is long and fast with the riders accelerating at high lean angles, and the stresses demand a special heat-resistant construction so that the asymmetric rear tyres can cope with the excessive forces.
“We have seen in the past that the cold and rain can be important factors so softer compounds are generally required to generate good grip. Warm-up performance in the right shoulders is also important as the stresses on this side of the tire are fairly low.”
Bridgestone slick compounds available: Front: Soft, Medium. Rear: Medium, Hard (Asymmetric)
Bridgestone wet tire compounds available: Soft (Main), Hard (Alternative)