The iconic Silverstone circuit in the UK hosted Sunday the 12th round of the 2013 MotoGP Championship.
And though the 20-year-old rookie Marc Marquez was a favorite due to coming off a four-race winning streak, the Respol Honda rider was beat to the line by a mere 0.008 of a second.
The man who beat him? Yamaha Factory Racing’s Jorge Lorenzo. This was the reigning MotoGP Champion’s fourth win of 2013 MotoGP. Takng the final podium position was Marquez’s teammate, Dani Pedrosa.
The different temperatures after changing the British Grand Prix from its normal June meeting to one on Sept. 1 provided different conditions for the spec-Bridgestone tires. Due to this, and more traction available, the fastest riders were posting laps over a second quicker than normal.
Following is a Bridgestone tire debrief with Masao Azuma, the Chief Engineer of the Bridgestone Motorsport Tire Development Department:
Q. The qualifying and race lap records at Silverstone were smashed last weekend. Can you explain this big improvement in the general pace of the MotoGP bikes at this circuit?
Masao Azuma says: “A lot of the improvement had to do with the dry, consistent weather we had over the weekend. This enabled the teams to find a setup that got the most out of the tires and put it good use when it was needed most.
“We knew the one-thousand cc MotoGP bikes had the potential to go extremely quick around Silverstone and with our tire allocation for this race featuring rubber compounds towards the softer end of the scale, the potential for a big reduction lap times was good. However, to see the existing Circuit Best Lap record beaten by almost two seconds in qualifying and the Circuit Record Lap lowered by almost a second in the race was outstanding.
“It is good to see such pace over a lap but for Bridgestone, we were most pleased with the overall race time which was about 24 seconds quicker than last year, representing an improvement of over one second per lap compared to the previous best time. This shows that the high pace was maintained through the race with a minimal degradation of performance over the 20 laps.”
Q. There was a lot of variation in tire choice for the race, both for the front and the rear. Can you explain what it is about Silverstone and the tire allocation for this race that caused this?
Masao Azuma says: “The rear tire allocation for Silverstone is like the circuit, quite unique in that for the works riders we use the same, medium rubber compound on the ‘harder’ shoulder, which is the shoulder that is placed under the most stress while cornering which for this circuit is the right shoulder.
“We do this because our data indicates that the stress placed on the right shoulder is not so severe, so we don’t need to go harder than the medium compound on that shoulder. However, our asymmetric slicks need to ensure good temperature retention and warm-up performance on the lesser used ‘softer’ shoulder, which at Silverstone is the left side, so we use softer rubber compounds on that shoulder.
“So even the hardest option rear slick at Silverstone featured the medium rubber compound and as this compound has proved very popular this season. Another important factor was that all the afternoon sessions featured the same weather conditions and we had no rain. We have had a few instances this season where the harder rear slicks have been used in the afternoon practice sessions, only for conditions for the race being cooler, which has dissuaded the riders from selecting the harder rear slicks.”
Q. The number of incidents seemed to increase in the morning sessions. Was this just because of the cool weather or were there other factors at play?
Masao Azuma says: “Cooler temperatures always create more challenging conditions, there is no doubt about that but Bridgestone has made a big effort in recent seasons to improve both the warm-up performance and feel of our tires to reduce risk in cooler temperatures.
“On Friday, MotoGP was the only class not to have any crashes in the morning session and on Sunday morning, three of the five crashes happened at Vale which features a small dip which can unsettle the front of the bike in what is quite an extreme braking zone. This point of the track has always been challenging for the riders, and the cold weather exacerbated the situation.
“As always we will examine rider feedback, tire and telemetry data to see if changes need to be made for the future, but with the harsh braking zones at Silverstone if you go too soft with the compound selection, braking stability can become an issue. Front tire selection at Silverstone is always a juggling act, and I believe we got the balance right but there is no denying that in cool conditions, parts of the Silverstone circuit will always be difficult for riders to manage.”
Bridgestone slick compounds available: Front – Soft & Medium; Rear – Soft, Medium-soft & Medium (Asymmetric)
Bridgestone wet tire compounds available: Soft (Main), Hard (Alternative)
