US Grand Prix, Laguna Seca: Bridgestone Debrief with Hirohide Hamashima

For the 2011 edition of the United States Grand Prix, Bridgestone selected softer rear slick tyre compounds as part of a continued bid to respond to rider feedback and provide improved warm-up performance in cold conditions. Based very close to the Californian coastline, the conditions at Laguna Circuit are hot and dry in the afternoon, but in the morning the region is shrouded in a marine layer or dense mist that means the temperature is much lower until the sun burns it off around midday. The difference between track conditions from morning to afternoon can be over 20 degrees Celsius, making it a challenge for tyres to perform consistently across such a wide temperature gap. Casey Stoner fought from an early third position to pass Dani Pedrosa at the midpoint of the race and then Jorge Lorenzo on lap 27 to take victory, lapping remarkably consistently throughout. His fastest time on lap 3 and his effort on lap 29 were different by less than 0.2seconds.

Bridgestone slick compounds available: Front: Medium, Hard. Rear (asymmetric): Soft, Medium

Hirohide Hamashima – Assistant to Director, Motorsport Tyre Development Division

Bridgestone selected softer rears this weekend – how did this work out?
“I am very happy with our revised rear tyre compounds at Laguna this year as we could see that warm-up performance of the softer rear in the cold morning sessions was markedly improved, yet still it was a viable option for the race with 12 riders deciding to use it. Rider feedback was positive too. Valentino said: ‘I’m pleased that Bridgestone brought some soft tyres, which worked well in the cool temperatures [in the] morning’ and Colin also commented: ‘I want to say a big thanks also to Bridgestone. They agreed to bring some softer tyres for this weekend and it was definitely the right choice’. Our aim was and is to listen to the riders’ comments and feedback and provide them with tyre options that they feel more comfortable with in cool conditions and I am satisfied that we achieved that this weekend.

“The results show that the harder options as used by Casey, Jorge and Dani were faster in the race, but I am very happy that so many riders decided they could use the soft compound rear tyre on Sunday afternoon. Based on tyre performance and feedback this weekend, I am confident we are on the right track in our proposal to select softer rear tyres for five of the remaining eight races this season to improve warm-up performance and rider feeling in cold morning conditions.”

What did it mean for riders’ race tyre choices?
“Even though we brought the soft and medium rear tyre compounds this year instead of the medium and hard as we did in 2010, there was a good mix of riders using both specs in the race. The front-runners used the harder option for its extra durability and consistency, but the majority of the field actually chose the soft rear tyre, confident that it would last race-distance satisfactorily. Ben was the highest-finishing rider to use the softer rear, claiming fourth position. He set the sixth fastest lap of the race, behind the five riders who opted for the harder rear, but ultimately his consistency was good and he passed Andrea, who was using a harder rear, at the end of the race.

“Warm-up performance was not an issue for the race because of the high track temperature, and most of the riders recorded their best times within their first five laps, including Casey who set the fastest laptime on lap 3. What all of this shows is how certain bike and rider packages work better using our softer compounds, and the importance and effect of bike setup and riding style on tyre wear.”

Source: Bridgestone Motorsport