San Marino Grand Prix, Misano: Bridgestone Debrief with Shinji Aoki
Jorge Lorenzo claimed his third consecutive MotoGP™ victory at Misano after the Yamaha Factory Racing star won the San Marino Grand Prix ahead of the Repsol Honda duo of Marc Marquez and Dani Pedrosa who finished in second and third place respectively.
Dry weather was present for all three days of the race weekend, with Sunday experiencing slightly cooler conditions which kept track temperatures to a mild 31°C for the race. The lower race day temperatures and reports of poor tarmac grip levels from the riders resulted in most of the grid choosing softer rear slick options front and rear for the race, with only seven of the twenty-four starters selecting the harder front slick option. A MotoGP™ group test took place on Monday at Misano, with Bridgestone supplying an experimental rear slick for evaluation by the works riders.
Bridgestone slick compounds available: Front: Medium & Hard. Rear: Soft, Medium & Hard (Asymmetric)
Bridgestone wet tyre compounds available: Hard (Main), Soft (Alternative)
Q&A with Shinji Aoki – Manager, Bridgestone Motorsport Tyre Development Department
What is your assessment of tyre performance at the San Marino Grand Prix?
“Overall I am happy with how our tyres performed at Misano. This is not the most severe of circuits in terms of its severity on tyres, but the low grip and high abrasion level of the tarmac, combined with the bumpy surface makes this circuit especially sensitive to bike setup to ensure the maximum performance is extracted from the tyres. With all these factors considered, we had to devise a tyre allocation that could provide enough grip and stability while ensuring good wear resistance. Although the ambient temperatures on Sunday were cooler than earlier on the race weekend, thankfully the weather was dry and consistent for all three days which gave the teams and riders ample time to work on bike setup. Our tyre allocation for the race worked well and it is always pleasing to see a new Circuit Best Lap record being set and the overall race time was also six seconds quicker than the old record, so it appears most teams were able to find a setup to get the most out of the tyres on the less than ideal track surface.”
Many riders complained about the condition of the tarmac at Misano this year. As a tyre supplier, how do you compensate for this with the tyres?
“It is true that many riders said that the condition of the Misano surface was worse this year than in previous races here. In some situations if the asphalt is slippery you would provide softer rubber compounds as they provide more grip. However, Misano is not only slippery and bumpy, yet also quite abrasive so we cannot use rubber compounds that are too soft as excessive tyre degradation could then become a problem. Also, the faster parts of the track, such as the section from Curvone through to turn 14 require a lot of tyre stability, which also suggests the use of harder compounds. To get the balance right, for the front tyre we waited until just before the race weekend before locking in our front slick compound allocation. This worked quite well as it gave us a clearer indication of what the ambient temperature would be and what compounds would work best. Our rear tyre allocation was also chosen to give the best balance of performance and durability, although the lower than anticipated grip level of the circuit and cooler temperatures on Sunday meant no riders selected the harder rear slick options for the race.”
Bridgestone brought a new experimental rear slick to Misano for the post-race test. Can you explain some of the technology and what the benefit this new development brings?
“The experimental rear slick we brought was a new specification of hard compound rear slick which we developed to improve the grip on the edge of the tyre. In order to enhance the edge grip of the hard rear slick, we tried a new structure at the edge portion of the tyre. The feedback from this experimental slick was very positive and we will now analyse the data we acquired from the test, after which we will liaise with Dorna, FIM and the teams about where and when we can introduce this new rear slick option.”
Source: Bridgestone Motorsport