Bridgestone announced during the Sachsenring weekend that a proposition for the revision of the MotoGP tyre allocation had been made to the Safety Commission.
Following the ninth round of the 2011 season Hirohide Hamashima, Assistant to Director of the Motorsport Tyre Development Division at Bridgestone, analysed the performance of the slick compounds offered throughout at the eni Motorrad Grand Prix Deutschland.
What happened on Friday morning?
“There were several crashes in which Valentino (Rossi), Casey (Stoner), Dani (Pedrosa) and Toni (Elías) all fell. In each instance it was through a right hand corner, and of course with only three rights in a lap it is the right side of the tyres that is lesser used and therefore tends to be cooler. Every crash happened as a result of the rider losing the front end. Turn eleven, where most of the falls occurred, is the first fast right of the lap and is over a blind crest before riders plunge downhill towards turn twelve. This means a few things: because it is the first fast right of the lap, the right side of the tyres hadn’t been subject to much residual load by that point so the temperature tends to be lower. It is a fast corner so the riders must commit to it and carry a lot of speed through it, which places sudden load on the front tyre. And finally, because it is over a blind crest, there is a natural tendency for the bike to go light which means as the circuit drops away the load exerted through the tyres is momentarily reduced, reducing contact patch and therefore grip. Plus, the track temperature was cold, and the combination of this contributed to the crashes we saw on Friday morning.
“It is important to point out though that we must select our tyre compound options for the conditions we expect in the race which are often if not always much better. Indeed, in the race our compound options were very well suited and performed very well. After Friday morning there were no repeat instances of the same situation so it is fair to say that the conditions on Friday morning were unique and unfortunate as we never like to see riders crash and make great efforts when developing and testing our tyres to make rider safety paramount.”
Softer rear slicks were selected for the German GP this year – what can you say about tyre performance?
“I am very happy with tyre performance in the race because we were able to see that riders could use both specs of front and rear tyres very well and the times and consistency were very good. Dani set a new lap record on the harder front and rear options, first on lap 9 indicating the performance was good from an early stage, and then finally on lap 20 indicating that the performance lasted well over race distance. The consistency from the top three in particular was also very impressive as they set mid-to-low 1’22s lap after lap from the first flying lap until the chequered flag. This resulted in the top three all recording race times faster than the previous total race time record which is a very good sign of tyre consistency and durability, as well as of course the consistency and talent of the riders.
“Then we could also see that Álvaro (Bautista) used the softer front and rear slicks for the race and was also very consistent and gave a good performance. Racing very closely with Valentino, Nicky (Hayden) and Colin (Edwards) until the finish, all of whom used the harder options, Álvaro had no problems with tyre wear or graining even on a circuit as severe as Sachsenring.
“We have selected softer slicks for many of the remaining races this year and based on the performance of this weekend’s revised rear tyre selection, combined with the changes to tyre allocation that we have proposed from Brno onwards, I am satisfied that we are moving in a good direction for warm-up performance and rider feeling.”
source: MotoGP Official Website
source: MotoGP Official Website
