Spanish Grand Prix, Jerez: Bridgestone Debrief with Masao Azuma

Round two of the 2012 MotoGP™ season produced a thrilling encounter at the Circuito de Jerez with the unsettled weather conditions not dampening the spirits of the huge crowd that gathered to cheer on the first European race of the season.

Reigning MotoGP champion Casey Stoner rode his Repsol Honda RC213V to a first ever victory at the Jerez circuit ahead of Yamaha Factory Racing’s Jorge Lorenzo in second place, while Repsol Honda’s Dani Pedrosa was third.

Rain fell throughout the weekend minimising dry-running time and conditions for the race were less than ideal with some damp patches on track following an early afternoon downpour that resulted in the Moto2 race being prematurely ended under a red flag.

Bridgestone slick compounds available: Front: Soft, Medium, Hard. Rear: Soft, Medium.
Bridgestone wet compounds available: Hard (Main), Soft (Alternative).

Q&A with Masao Azuma – Chief Engineer, Bridgestone Motorsport Tyre Development Department

Weather conditions were extremely variable over the race weekend at Jerez. How did the tyre options selected for the race perform in these challenging conditions?
“The intermittent rain that fell over the weekend caused the track to be damp, but not fully wet at times which aren’t ideal conditions for wet tyres. However we have experienced such conditions before at Jerez both during last year’s race and during pre-season testing, so after analysing tyre data we decided for this race to make the hard wet compound the main wet tyre available to riders. The decision to make the main wet tyre the hard compound was validated during Friday practice as the extra durability of this option allowed it to more effectively deal with what were damp track conditions with no standing water.

“The slick tyre options we provided performed very well in the race, with the soft rear slick tyre providing good warm-up performance in the cool conditions while showing consistent grip levels throughout the 27-lap race. Both front slick tyre options used in the race worked well, with the top three riders using the medium compound front slick tyre while the fastest lap of the race was set by a rider utilising the new specification front slick tyre in the hard compound.”

With the wet weather at Jerez, how did the recent change in wet tyre allocation regulations affect tyre choice?
“The change in regulations meant that riders could choose up to two front and two rear wet tyres in an alternative compound which for Jerez was the softer compound. Many riders selected this softer option as part of their allocation, but mainly for use in qualifying if conditions were wet. As qualifying turned out to be dry, the softer spec wet tyre was used by some riders in Sunday warm-up but had the race been wet, it is more likely that riders would have used the hard compound wet tyre for its better durability.

“What was revealed this weekend is that riders appreciate having an extra option of wet tyre as it gives them greater flexibility with their tyre choice when dealing with variable weather conditions and so this new regulation is already proving to be beneficial to riders.”

For the race, most riders chose the new specification front slick tyre in the hard compound, while the rest of the field selected the medium compound. What benefits did one option offer over the other?
“Unfortunately due to the bad weather, riders didn’t have adequate time to test every option of slick tyre offered, though the two front slick tyres chosen by the riders performed well during the race. The medium compound front slick tyre warms-up faster than the harder option and as riders were not sure if light rain would fall during the race, the medium compound slick tyre would deal better with a reduction in track temperature compared to the harder compound.

“The harder option offers rider greater durability and every rider that chose the harder compound option did so in the new specification front tyre that made its first race appearance at Jerez. Those riders who tried the new specification front slick tyre during qualifying claimed it immediately felt better due to the greater feel it offered through the front-end. Some riders who didn’t get the chance to try the new specification front slick tyre during qualifying still selected it for the race as they had previous good experiences with it at the Jerez IRTA test in March. This is very encouraging as it shows that the new front slick tyre fulfills its key technical objectives of providing enhanced rider feel and improved warm-up performance.”

Source: Bridgestone Motorsport