Q&A with Masao Azuma – Chief Engineer, Bridgestone Motorsport Tyre Development Department.
Last weekend was the second race at Circuit of The Americas. How have track conditions developed in the year since the first race here? “The grip levels of the track were better than in 2013 but overall the circuit has not changed much from last year. Some riders noticed it was bumpier in some sections of the track, particularly in the hard braking zones but the character of the circuit is basically the same. The better grip levels and the fact that riders had last year’s data to work with meant that the pace during the Friday practice session was much quicker than last year. This quick pace continued throughout the whole race weekend with new circuit records being set in qualifying and the race, and the overall race time being almost ten seconds quicker than last year.”
A number of factory Honda and Yamaha riders evaluated the hard compound rear tyre but in the end, only one rider Marc Marquez selected it for the race. Can you explain why more riders didn’t choose this option for the race? “We were expecting more riders to use the hard compound rear slick for the race, but as track temperatures were a lot cooler for the race than the other afternoon sessions and there were also the possibility of some further rain, there may have been a shift among the factory riders to the medium compound rear.
“Compared to the hard rear we offered at this circuit last year which Marquez also used to win the race, the 2014 specification hard compound rear slick has been engineered for greater edge grip. This improvement means that I expect more and more riders will use this as a race option at future races this year. Marc was very fast on the hard compound rear slick even in the morning sessions, so I think he was comfortable using this tyre for the race even if the conditions were cooler than expected.”
Some riders experienced high levels of abrasion on the medium compound front slick during the race. Was this something that occurred earlier in the race weekend and can you explain why this happened? “The high abrasion on the right side of the front tyre that some riders experienced during the race was unexpected. There are some sections of the circuit that are quite demanding on the right side of the tyre, but our compound allocation for this race was designed to meet these demands. We need to look at all the variables including riding style, machine character and the track condition during the race to work out why we had such high levels of abrasion during the race, and why some riders were affected more than others. We can say with confidence that the tyres were not in any way faulty, just that the operating conditions during the race were a lot harsher when compared to last year and the practice sessions earlier in the race weekend.
“As we didn’t see these very high levels of abrasion last year or during practice and qualifying this year, the tyres and race data from the Americas Grand Prix will be analysed at our Technical Centre so that we can find out why this happened.”