Aragon Grand Prix, Motorland: Bridgestone debrief with Shinji Aoki

Last Sunday’s Aragon Grand Prix was won by Repsol Honda’s Dani Pedrosa, the Spaniard finally winning at the circuit after finishing runner-up the previous two years.

In what has been an almost regular occurrence this season, bad weather affected the first couple of days of action at Aragon, requiring wet tyres to be used for the first three sessions. The rain did clear for Sunday, but temperatures were still not high for the race with a peak track temperature of thirty degrees Celsius recorded. The limited dry track time and moderate track temperature meant that tyre choice for the race was consistent throughout the grid, with all riders opting for the softer rear slick and all but three riders selecting the harder front slick.

Pedrosa’s Aragon victory was his fourth of the year and closes the gap to Yamaha Factory Racing’s Jorge Lorenzo to thirty-three points with four rounds remaining. This latest win takes Pedrosa’s current points tally to 257, making 2012 his most successful season in the premier class of Grand Prix racing.

Bridgestone slick compounds available: Front: Soft, Medium, Extra-Hard. Rear: Medium, Hard (Asymmetric)
Bridgestone wet tyre compounds available: Soft (Main), Hard (Alternative)

Q&A with Shinji Aoki – Manager, Bridgestone Motorsport Tyre Development Department

No riders used the extra-hard front slick in qualifying and few tried it in warm-up, yet it was used by almost all riders for the race. Can you explain why the extra-hard was so popular for the race, particularly as it wasn’t tested earlier on the weekend?
“Track temperatures for qualifying and warm-up were very low at Aragon at less than sixteen degrees, and not within the operating zone for the extra-hard front slick, so those riders that did try them during warm-up only did so to scrub them for the race. Aragon has a couple of hard braking zones as well as some fast sections which load the front tyre considerably, and the harder front slick option provides greater stability in these areas, making it a desirable option for riders if conditions allow its use. Track temperatures increased throughout the day and by the start of the race were within the operating zone for the extra-hard rubber compound, and this is why most of the riders went for this option. Furthermore, some of the top riders tested at Aragon at the beginning of September and tested the extra-hard front substantially at that time. This was a main factor why the race winning time was seven second faster than last year, even though there wasn’t a lot of time over the weekend to set up the machines.”

“Aragon was another race weekend when the lack of dry track time and variable weather conditions meant tyre choice for the race wasn’t confirmed until the formation of the starting grid and if track temperatures for the race were the same as qualifying, I believe more riders would have selected the softer of the two front options; the medium compound slick.”

The raise in temperature on Sunday had little effect on tyre choice for the rear however, with all riders preferring the softer, medium compound rear slick. Why didn’t anyone select the harder rear option for the race?
“This year’s race was the first time we offered rear slicks in an asymmetric configuration and the softer rear slick option for Aragon was the medium compound. Our medium slick has a wide operating temperature range and in conjunction with the asymmetric construction optimised for the Aragon circuit, performed well over the full range of track temperatures experienced over the weekend. I think we would only have seen riders use the harder rear slick at Aragon if track temperatures approached those seen in testing, which were around twenty degrees warmer than on Sunday. Also, riders commented that grip levels on the circuit were still not the best, so going with the softer of the two options ensured better edge grip and warm-up performance from the start of the race.”

Source: Bridgestone Motorsport Press Release