Dutch MotoGP debrief with Masao Azuma

At last Saturday’s Dutch Grand Prix, Movistar Yamaha MotoGP’s Valentino Rossi consolidated his lead of the MotoGP championship standings with a hard-fought victory over Repsol Honda Team’s Marc Marquez and fellow Movistar Yamaha MotoGP rider Jorge Lorenzo who finished in second and third place respectively.
 
It was a record-breaking weekend at Assen with Rossi setting a new Circuit Best Lap record (1'32.627) in qualifying, Marquez setting a new Circuit Record Lap (1'33.617) during the race and the overall race time (40'54.037) beating the old mark by over twenty seconds. Weather conditions for the race were dry with a peak track temperature of 32°C recorded during the twenty-six lap contest.
 
Q&A with Masao Azuma – Chief Engineer, Bridgestone Motorcycle Tire Development Department
 
We saw many records smashed at this year’s Dutch Grand Prix, are you happy with how the weekend went for Bridgestone?
 
“Yes it was a positive weekend for us, not just for the very quick pace shown by the riders but also we had relatively few incidents and our tire allocation worked well for everyone. At Assen, it is important to bring a rear tire allocation that can withstand high temperatures and loads, yet still provides enough grip and consistency for the riders and in this regard, I think we delivered. Assen can experience quite a range in track temperatures between the morning and afternoon sessions and our front tire allocation provided enough options for the riders to negotiate this change comfortably. It was a record-breaking weekend at Assen at what is a challenging circuit for tire development, so I am happy with our performance.”
 
Only one rider, Marc Marquez selected the medium front slick for the race. Were you surprised that more riders didn’t select this option?
 
“I wasn’t surprised that the medium compound front slick wasn’t used by more riders, as traditionally riders prefer softer front options at Assen as they want as much cornering grip as possible. We’ve only offered the medium compound front at Assen for the last couple of years, and this year Marc was only one of two riders to try the medium compound front slick on Friday and he felt it gave better braking stability without sacrificing too much cornering performance. He was very quick in the Saturday morning Warm Up session using the medium front and even though track temperatures for the race were a bit lower than in FP4, he felt this was the best option for him. For the other riders, the preferred to race on the soft compound rear which doesn’t have the braking stability of the medium option, but offers better cornering grip and warm-up performance.”
 
Assen is a very severe circuit for the rear tire with some very fast sections. What is it about this circuit that makes it so tough for the rear tire and does this require a special approach to tire development?
 
“The Assen circuit is quite severe on tires due to its fast corners and the high camber in some of the quicker sections, but we also need to ensure our rear tires offer high levels of grip. This banking significantly increases the load on the rear tire which means we have to take a special approach to tire development for this circuit to ensure maximum safety for the riders. At many circuits we provide rear slicks that feature a slightly modified construction to improve edge grip, but the severity of the Assen circuit means we are unable to provide this specification of rear slick at the Dutch Grand Prix. Instead, we ensure we offer a tire allocation with compounds that offer the best balance of grip, durability and heat resistance. Not only did we see record pace all weekend at Assen, we experienced no abnormal wear with our tires so it seems our compound allocation was well matched to the conditions we had at Assen last weekend.”