Mugello MotoGP | Bridgestone Tire Debrief
2013 MotoGP Championship Tire Analysis
The 2013 MotoGP Championship headed to Italy last weekend for round five of 18 at Mugello in the Tuscany region.
The circuit – one of the fastest on the MotoGP championship with straight-away speeds over 215 mph – is harsh on the Bridgestone tires, demanding optimal setup for positive results.
A few riders and their perspective teams found this optimal setup, including Yamaha Factory Racing’s Jorge Lorenzo, who took his third consecutive win at the circuit.
Lorenzo was joined on the podium by the current points leader, Repsol Honda’s Dani Pedrosa, and Monster Yamaha Tech 3’s Cal Crutchlow.
Following is a Q&A with the chief engineer of Bridgestone Motorsport Tire Development Department, Masao Azuma, discussing Mugello MotoGP.
Q. All of the rear slicks brought to Mugello this year featured Bridgestone’s heat-resistant construction. Can you explain why these tires were supplied and did they do the job last weekend?
Masao Azuma says: “After the new 1000cc MotoGP machines were introduced last year, Bridgestone reviewed its tire severity rating for every circuit on the calendar.
“These ratings are based on the number of right and left-handed corners, the type of asphalt used and many other factors that contribute. Using this rating system, Mugello has always been one of the more severe circuits in MotoGP for tires, but the increase in loads generated by these heavier, more powerful motorcycles increased the stress endured by tires at this circuit to a point where the heat-resistant construction was needed.
“As a result, we decided that for this year, the best decision for the safety of the riders was to supply all our rear slicks at Mugello in our heat-resistant construction.
“Also, as we are supplying rear slicks to the CRT riders this year that are one step softer than the works riders, it means for the first time our soft rubber compound was used on the right shoulder of a rear slick option at Mugello.
“The use of this soft compound on the right shoulder means we decided to use heat-resistant construction for the CRT-specific slicks for safety reasons as well, and the results were as we expected; quite positive.
“Some riders do notice a slight difference in grip from the edge of the tire with this heat-resistant construction compared to our regular slicks, however, the performance these tires offer is still extremely high. Proof of this point was that new qualifying and race lap records were set at Mugello last weekend using the heat-resistant rear slicks.”
Q. With some circuits on the calendar being harsher on tires than others, why doesn’t Bridgestone need to create heat-resistant front slicks at the more severe circuits?
Masao Azuma says: “The rear tires on a motorcycle are subjected to much more stress than the front tires. The front tires have to deal with cornering and braking forces, however the rear tires also have to cope with transferring the power to the ground when the bike accelerates and it is this that creates very high temperatures. Front tire temperature increases when braking, but the total braking time for one lap is usually much less than the time spent accelerating.
“The range of temperatures a front tire is subjected to during a race is a lot less than the rear tire. Therefore, even at those circuits that are the most severe on front tires such as Aragon and Sepang, our regular construction front slicks are more than able to cope with the stresses placed upon them by the MotoGP machines.”
Q. The 2013 Italian Grand Prix was held earlier in the year than usual, did this have much bearing on the tire allocation for this year?
Masao Azuma says: “Reviewing the historical data we could see that generally track temperatures at Mugello are quite high, but this year not only was the race held earlier, mainland Europe has experienced unusually cool weather this spring.
“We considered these factors when deciding on our tire allocation for the Italian Grand Prix, particularly for the front slicks. In fact, we waited until the Wednesday before the race weekend to lock in our front tire allocation, as we wanted the most accurate predictions of what the weather would bring.
“If the weather conditions for the weekend would have been much warmer, than we considered offering a selection of front slicks one step harder than originally intended. However, in the end our original front tire allocation worked well as track temperatures on Friday morning were very cold, and so we had to make sure the riders had front tires that warmed up as quickly as possible on a track that was quite greasy due to the recent rain. Basically, we kept our original tyre allocation for Mugello, though we were prepared to change it just before the race weekend if required.”
Bridgestone slick compounds available: Front: Soft & Medium. Rear: Soft, Medium & Hard (Asymmetric)
Bridgestone wet tyre compounds available: Hard (Main), Soft (Alternative)