The Bridgestone press office released the following question and answer session with their Director of Motorsport Tire Development, Hirohide Hamashima:
Spanish Grand Prix debrief with Hirohide Hamashima
Round 2: Spanish GP – Post-race debrief
Jerez Circuit, Thursday 7 April 2011
Bridgestone slick compounds available: Front: Medium, Hard. Rear: Soft, Medium
Bridgestone wet compounds available: Front: Soft. Rear: Soft
The Spanish Grand Prix started with the bright sun and fine weather the Andalucían venue is known for, but on Sunday the rain arrived and the first European GP of the season was also the first wet race since the Malaysian GP in 2009. Early on in the weekend the laptimes were very fast and several riders dipped under the lap record. The race however started wet so every rider used Bridgestone's wet tyres for the first time since the Portuguese GP last year, but as the track started drying by the end of the race the conditions became very tricky. The race was punctuated with crashes with several of the front-runners falling, handing Jorge Lorenzo a dramatic victory ahead of Dani Pedrosa and Nicky Hayden.
Q&A with Hirohide Hamashima – Director, Bridgestone Motorsport Tyre Development
The laptimes in the dry were very impressive, especially during qualifying. Why were they so fast?
"Track conditions were good on Friday and Saturday which was a large factor, and the temperature was also neither too hot or too cold. Immediately on Friday morning the times at the front were fast, although free practice two on Friday afternoon was slower as by then the wind had picked up and was quite strong, and the gusts made it difficult for the riders. But again on Saturday morning in the final free practice the times were very fast again. On just his second flying lap Dani Pedrosa was faster than the existing lap record, and his third lap was 0.9seconds faster than it. By the end of the afternoon's qualifying session, Casey Stoner was a full one second faster than the lap record, so from this I can say that clearly slick tyre performance was good, coupled with a track temperature of 33 degrees Celsius, good track conditions and very little wind. It also demonstrates the result of the development work undertaken by the teams over the winter."
The race of course was run on wet tyres though which was the first day of wet running this season. What challenges did this pose?
"Well the morning warm-up session was the first time that the teams have used our wet tyres with their 2011 bikes, and also for the MotoGP rookies it was their first time riding in the wet on our tyres too. The warm-up gave them just 20 minutes of running to arrive at good setups for the race which was a great challenge, despite the fact that all manufacturers have a great deal of data at the Jerez circuit from past races and tests here. From our side, the main role was to work closely with the teams and riders to support them in their setup decisions and provide them with any data that we could to help with this process. There was no concern for tyre selection however as under the current regulations we can only select one wet tyre compound for each grand prix, so every rider must use the same."
The race itself was very difficult, both for riders and tyres, because of the conditions. What can you say about wet tyre performance?
"Actually I can say that I am satisfied with the way our wet tyres worked in very difficult and demanding conditions. For sure tyre wear was quite high, but this is because the circuit was becoming increasingly less wet throughout the race and the tarmac at Jerez is abrasive, both of which lead to a higher level of tyre wear. The grip level dropped throughout the race but it did so consistently which made it a little easier for the riders to manage. I can say that the conditions we saw in Jerez were unusual and very tough for our tyres; the toughest situation we can expect to see. I am happy with our wet tyre selection too because compound selection is always a balance between grip level and tyre life, and in such slippery conditions the soft wets provided more grip and riders will always prefer a safer level of grip rather than a tyre that can last much longer but offers no traction. Even if we had the hard compound wet available in Jerez, I believe not many riders would have chosen it because the start of the race was full wet, and even if they did in such tough conditions it would only have given a few more laps."