Bridgestone issued the following press release discussing the Italian Grand Prix at Mugello, and the findings from the one-day test on the Monday following Mugello:
Italian Grand Prix and Official Test debrief with Hirohide Hamashima
Round 8: Italian GP – Post-race debrief
Mugello Circuit, Tuesday 5 July 2011
Bridgestone slick compounds available: Front: Medium, Hard. Rear (asymmetric): Medium, Hard
Wet compounds available: Front: Soft. Rear: Soft
The Italian Grand Prix was the eighth round of the season and the sixth to have at least one MotoGP session interrupted by rain. After dry and hot starts to Friday and Saturday, each afternoon brought rain that cut short both the second free practice and the qualifying session. The race however was run in dry conditions. This year Mugello has been completely resurfaced and the new tarmac is very good – high grip and also much smoother with all the bumps of the old surface removed completely. This, coupled with the fact that Bridgestone brought asymmetric rear slicks to Mugello for the first time in the single tyre era, meant that the laptimes were fast and a new lap record and total race time record were set. Jorge Lorenzo overcame an initial lead by Casey Stoner to take his second victory of the season and his first at the Italian venue in the premier class. Andrea Dovizioso was second and Casey Stoner third, meaning that now the championship points standings have gotten a little closer. The Grand Prix was followed by an Official IRTA one-day test at the venue on Monday.
Hirohide Hamashima – Assistant to Director, Motorsport Tyre Development Division
Bridgestone selected asymmetric rear slicks for Mugello this year – what was the feedback?
"Rider comments about our asymmetric tyres at Mugello over the weekend were positive. At this circuit in the past we have seen that it isn't strictly necessary to have asymmetric tyres, evidenced by the lap record that Dani Pedrosa set last year on symmetric rear tyres – which means both shoulders are the same compound. However, we also know that the riders like our asymmetric tyres and the improved feeling offered by the use of the softer compound in one shoulder, and this is why we have increased our usage of them year-on-year.
"Warm-up performance here was never going to be a real issue because of the temperature and the level of abrasion of the tarmac, so our choice to bring asymmetric rears was more for grip performance and rider feeling rather than safety. The softer left shoulder gave the riders better feeling and grip through the left-handers, of which there are six as opposed nine rights, and this gave them a little more confidence in the tyres and in edge grip."
What can you say about the new surface at Mugello from a tyre perspective?
"The new tarmac makes the circuit much smoother than it used to be with less undulation, and it is also high grip. The reduction in bumps means that generally the bikes are less unsettled and the tyre contact patch is more constant, so the bike feels more stable. This is one contributing factor to the faster lap times. Another is that the tarmac is high grip, the benefits of which are clear in terms of corner speed and braking and acceleration forces. This means though that the stress and loads on our tyres were much higher this year, but still tyre wear was as we expected and in general I am pleased with tyre performance. Our usage of asymmetric rear slicks this year was a third contributing factor to the laptime improvements, though of course bigger changes will always come from a brand new surface rather than a relatively smaller change to rubber compound."
What did Bridgestone test in the official post-race test?
"We tested one new front tyre compound during the official test day, and we provided one of these new tyres to each MotoGP rider. Several riders tested this new front tyre, which is important in our development of compounds for the 1000cc era next year. Rider feedback was good, and in fact Casey and Marco set their fastest laps using this new tyre. Casey was fastest overall, with a 1m 47.326s and Marco was second fastest just 0.096s behind, so both times are much faster than the pole record set on Saturday which is a good indication of performance. The test was important for us and we collected a lot of valuable data as we continue our development of our new family of tyres."