French Grand Prix, Le Mans: Bridgestone Debrief with Masao Azuma
Rain lashed the Bugatti Circuit at Le Mans prior to last Sunday’s French MotoGP™ and an exciting wet race ensued with Yamaha Factory Racing’s Jorge Lorenzo streaking away to take his second win of the season ahead of Ducati’s Valentino Rossi and Repsol Honda’s Casey Stoner.
Weather conditions at Le Mans started dry but cool on Friday but gradually degraded over Saturday and Sunday, with cold and wet conditions greeting riders as they lined up on the grid for the race. Track temperatures struggled to get over 20°C throughout the whole race weekend meaning that the softer compound tyres were preferred by riders due to their greater warm-up performance and initial grip.
Bridgestone slick compounds available: Front: Soft, Medium. Rear: Soft, Medium (Asymmetric)
Bridgestone wet compounds available: Soft (Main), Hard (Alternative)
Q&A with Masao Azuma – Chief Engineer, Bridgestone Motorsport Tyre Development Department
Race conditions were not only wet, but also very cool. How did this affect the performance of the wet tyres?
“The conditions for Sunday’s race were quite challenging for riders as grip levels in the wet at Le Mans are poor to begin with, but the added factor of very cool temperatures made grip even harder to come by. Bridgestone anticipated these kinds of conditions and hence made the main wet tyre the soft compound, but also gave riders the option of selecting a limited number of the alternative hard compound wet tyre in case we had conditions which were damp but not completely wet.
“Overall, the performance of our wet tyres at Le Mans was very positive and the soft compound wet tyre that was used extensively during the race gave riders the warm-up performance and initial grip required to race in the harsh conditions, but also provided enough durability to offer consistent grip levels throughout the race.”
Some riders tried the hard compound wet tyres during the wet Sunday warm-up session but didn’t select it for the race. Was the hard wet tyre a viable option for the race?
“Though we had rain on Sunday morning, it was difficult to understand if the rain would continue through the afternoon or would stop before the race. Therefore, riders took the opportunity in morning warm-up to assess the grip level of the hard compound on a track with standing water and we actually saw some good lap-times with the hard compound wet tyre and acquired valuable data on how these tyres behave in such conditions. As we saw, the rain continued steadily until the start of the MotoGP race and was not expected to stop, so in this situation where there was still plenty of standing water out on track and conditions were quite cool, all riders selected the soft compound wet tyre for the rear and all but one rider selected the soft compound wet tyre for the front.”
Most riders set their personal best lap-time towards the end of the race. Can you explain why this happened?
“As the standing water on the circuit was dispersed by the wet tyres the grip levels increased which is why lap times towards the end of the race began to improve. As grip levels increase, so does tyre abrasion but the durability of the soft compound wet tyres in these conditions was still good enough that the riders could take advantage of this increased grip to lower their lap times.”
Source: Bridgestone Motorsport