Portuguese Grand Prix debrief with Tohru Ubukata
Bridgestone slick compounds available:
Front: Soft, Medium
Rear (asymmetric): Medium, Hard
Bridgestone wet compounds available:
The weather at the Estoril circuit is always unpredictable because of its proximity to both sea and mountains and this year was no different, but the surprise worked in favour of the riders. Forecast to rain all weekend, Bridgestone’s wet tyres were only required in Saturday morning practice and Sunday’s warm-up. Rain did hit the circuit each night, but only after MotoGP running had finished. This meant that whilst the race was dry, as many riders had wanted after a soaked Spanish GP at Jerez, the circuit was greasy and slippery as the rain made it dirty each time. Having set the early pace for much of the weekend and starting from the front row for the first time in the premier class, Marco Simoncelli crashed out on the opening lap, leaving it to Dani Pedrosa and Jorge Lorenzo to fight for the victory, with the former taking to the top step with his first win of the year.
Tohru Ubukata – General Manager, Bridgestone Motorsport Tyre Development Department
How did the weather affect track conditions and tyre performance over the weekend?
“For both sessions on Friday the track was dry but quite dirty and greasy so did not provide the best grip. The tarmac of the Estoril circuit is quite bumpy and slippery anyway so in these conditions tyre performance was reasonable but the laptimes were about one second slower than the lap record. By the afternoon session, the track temperature had risen by ten degrees Celsius and with a morning of running the track was cleaner, and the laptimes fell by nearly half a second.
“Normally on the second and third days of running, the track continues to get cleaner and the grip gets better, but heavy rain on Friday, just after the afternoon session had finished, meant that all Friday’s cleaning was undone and on Saturday morning the track was damp and greasy again. Still, by the end of qualifying the pole time was down to within 0.2seconds of the lap record.
“Rain hit the circuit again on Saturday night though, leaving the warm-up session damp and the circuit greasy ahead of the race. Overall, I can say that circuit grip was lower this year, but this helped in the riders’ decisions to use the softer option rear slicks for the race as durability was not a concern and the extra grip of the softer compound was a definite advantage.”
None of the sessions were exactly wet, only damp. What can you say about wet tyre performance?
“Free practice on Saturday morning was damp and gradually dried although a dry line didn’t form and all riders used our soft compound wets for the whole time. For Sunday warm-up the track started damp and only right at the end of the session could slicks be used. Although it was still very slippery at the end of warm-up when Colin Edwards went out on slicks and set the fastest time, we could see that the wet tyres have sufficient operating range in wet to drying conditions to overlap with our slick tyres so I am happy about this.”