Laguna Seca MotoGP™ debrief with Masao Azuma
Bridgestone slick compounds available: Front: Soft, Medium, Hard. Rear: Soft, Medium (Asymmetric)
Bridgestone wet tyre compounds available: Hard (Main), Soft (Alternative)
The 2012 United States Grand Prix was won by Repsol Honda’s Casey Stoner, the reigning MotoGP™ champion taking the checkered flag ahead of Yamaha Factory Racing’s Jorge Lorenzo in second place and teammate Dani Pedrosa who finished third. The race was run at a fierce pace, with the overall race time being over six seconds faster than last year, while Pedrosa set a new record fastest lap on lap five of the thirty-two lap race.
Weather conditions for last Sunday’s race were fine with clear skies and a track temperature of 43°C. Tyre choice was quite varied, particularly at the rear, and due to the difference in weather conditions between the morning and afternoon sessions, many riders including race winner Casey Stoner made their final race tyre choice on the grid. Six of the twenty-one riders on the grid selected the harder compound rear slick, while eighteen riders selected the harder front slick for the race.
Lorenzo extends his lead over Pedrosa in the championship to twenty-three points, while Stoner’s win sees him remain in third place overall though he closes the gap to Lorenzo and Pedrosa to thirty-two and nine points respectively.
Q&A with Masao Azuma – Chief Engineer, Bridgestone Motorsport Tyre Development Department
Rear tyre choice for the race was a hotly debated topic over the weekend. In the end, both compound options were selected for the race, so what were the determining factors in rear tyre choice?
“During long runs in free practice and qualifying it was clear that both the softer and harder rear slicks were viable options for the race, but it would come down to which rear tyre better suited the bike setup and riding style of individual riders. Generally, harder rubber compounds give better durability, but with the right bike setup and race strategy, the softer option also provided consistent grip levels throughout the race at Laguna Seca.
“The race was won on the softer rear slick and the fastest race lap was set on the harder rear slick so the determining factors were riders selecting a tyre that provided the best feel, and what grip characteristics the rider preferred over the duration of the race. Also, many teams waited to see what the track temperatures would be for the race before making a final decision on the rear tyre, though conditions were almost the same as they were in the Friday and Saturday afternoon sessions. We can determine from the results that under the race conditions both compounds worked very well, though it is difficult to say which was the better choice.”
Weather conditions last weekend were typical for Laguna Seca; cool and cloudy in the morning and clear and warm in the afternoon. How did this affect tyre performance?
“The variable weather conditions at Laguna Seca can make things complicated for teams and riders, though this year our feedback from riders was that they had a very good feeling from the tyres even in the morning sessions. I believe the improved warm-up performance of the 2012 specification tyres enabled riders to quickly find their comfort zone at Laguna Seca, especially during the cool mornings, and this was particularly important given the increased power output of the new 1000cc machines around this technical circuit.”
The harder front slick tyre was the preferred option throughout the race weekend, with only three riders selecting the softer front slick. What benefits did the harder front slick offer at Laguna Seca?
“Laguna Seca is a circuit with quick changes of direction and elevation that loads and then unloads the front suspension is a very short period of time. As a result of this character, front-end stability is always sought by riders at this circuit and the hard compound front slick is better in this regard. As the harder option also still gave riders enough edge grip to cope with the demands of this circuit, it was the preferred front tyre for all the sessions and the race. A few riders however did prefer the feel of the softer front slick, so they chose to use this for the race.”