Dutch TT Grand Prix debrief with Tohru Ubukata Round 6: Dutch TT GP Post-race debrief Assen, Tuesday 29 June 2010 Bridgestone slick compounds available: Front: Soft, Medium. Rear: Medium, Hard (asymmetric) Tyre compound selection featured heavily during the 80th edition of the Dutch TT at Assen. Throughout the weekend riders were lapping competitively on each specification, and the race provided a direct comparison between the extra edge grip of the softer rear slick option and the additional traction of the harder option. Jorge Lorenzo took his fourth win of the season using the hard option, after coming under pressure in the early stages from Dani Pedrosa and Casey Stoner, both of whom were using the softer rear tyre. The circuit was slightly modified this season in the Ruskenhoek corner, and whilst the circuit length was shortened by only 13 metres, the new lap record set by Dani Pedrosa was two seconds faster. The track temperature was high, reaching 47 degrees Celsius, and the weather was fine throughout the weekend maximising the riders’ dry running time. Q&A with Tohru Ubukata – Manager, Bridgestone Motorcycle Tyre Development Department The riders’ rear tyre choices were mixed in the race; why was this? “Last year we brought soft and medium tyres to Assen, and almost all riders used the medium compound for its extra durability on the right side. This year we brought asymmetric tyres to Assen, and also went one compound step harder as part of our process of continual development and improvement. This means that this year the riders could choose the medium or the hard compound rears for added durability in the right shoulder, whilst the soft compound rubber in the left shoulders retained warm-up performance and edge grip on the left side. “Our objective for tyre development in the single tyre era has always been to increase their temperature operating range; that is the range of conditions and track temperatures in which each specification can perform well. Indeed, we were doing this even before our appointment as the single supplier. Our achievements in this area mean that we now have a good overlap of performance between our different tyre compounds, and as we saw in particular this weekend both the medium and the hard asymmetric rear tyres offered similar levels of performance. “Tyre choice for the race therefore came down to rider preference and machine setup. Jorge was able to extract maximum performance from the hard rear and benefit from its increased durability, whereas Dani and Casey were able to use the softer option and benefit from its increased edge grip and initial performance in the early stages of the race. Some riders and bikes use the tyres harder than others and generate higher tyre temperatures so we recommend either one of our tyre options based upon attaining the optimum tyre temperature for each rider, machine and tyre package.” There was no difference in front tyre choice however; what can you say about this? “Firstly, the front tyre options we brought to Assen were softer than the rear: we selected the soft and medium fronts whereas the rears were our medium and hard compounds. If the temperature was cooler, some riders may have used the soft front for its extra edge grip, but as it was with a track temperature in the race of 47 degrees Celsius, the harder front tyre provided greater braking stability and more consistent front-end feeling for the riders.” The modification to the circuit at the Ruskenhoek corner improved laptimes by two seconds: did it have any impact from a tyre perspective? “The change to the circuit layout didn’t impact upon tyre shoulder performance as although corner speed was higher through Ruskenhoek as a result, loads were not excessive and tyre temperatures were still well within operating range. I can say though that the affect it did have was under braking into the right hander after, Stekkenwal. Carrying more speed through Ruskenhoek meant heavier braking into Stekkenwal which created more load on the centre of the front tyre, which was another contributing factor to all riders using the harder front for the race.” More, from a press release issued by CAME Raceways Yamaha: MCCONNELL VICTORIOUS AS WESTMORELAND MAINTAINS CHAMPIONSHIP LEAD CAME Yamaha’s Billy McConnell secured his second win of the Fuchs-Silkolene British Supersport Championship at his home round at Mallory Park, holding off championship rivals Sam Lowes and team-mate James Westmoreland. Gearlink Kawasaki’s Ben Wilson took the hole shot off the line from McConnell and Westmoreland but by the third lap the CAME Yamaha of McConnell had taken the lead, passing into Gerrards before team-mate Westmoreland followed, taking second from the Gearlink Kawasaki on the sixth lap. The safety car was deployed when Leon Hunt crashed at the Esses and when the race resumed, McConnell held the lead to the finish. Westmoreland fought to hold on to second place but was forced to settle for third behind rival Lowes, which now means the pair are equal on points at the top of the standings, whilst McConnell is now just two points adrift. McConnell said: “It was a fantastic weekend for me and I have to thank everyone at CAME Yamaha for giving me the tools to do the job, as I desperately wanted to win at my home round. We built up the confidence following the win at Cadwell Park and now that is two in a row which has put me right up there in the standings. I had a great start to the weekend and took pole position so I was in a good place for the start of the race. I just went for it as I wasn’t going to give the win up for anything and pulled a bit of a gap and then the safety car came out and I couldn’t believe it. During the safety car period the clutch bracket broke and I didn’t think I would be able to finish with a win, but the Yamaha has a blip system which made it possible to continue. There is so little between myself Westy and Sam (Lowes) that now I can’t wait until Knockhill.” Westmoreland said: “I was disappointed not to be able to challenge Billy for the win and to finish third as I felt comfortable for the first three quarters of the race. I was riding hard but within myself, so didn’t feel any pressure. I was losing a little on acceleration and so was having to make it up the brakes, but over the last laps I couldn’t push as I would have wanted and I suffered as I dropped to third. I am still at the top of the standings, albeit jointly, so we just have to do everything we can to win for the CAME Yamaha team this weekend at Knockhill.” Fuchs-Silkolene British Supersport Championship, Mallory Park, race result: 1. Billy McConnell (CAME Yamaha) 2. Sam Lowes (GNS Racing Honda) +2.033s 3. James Westmoreland (CAME Yamaha) +6.030s 4. Glen Richards (Padgetts Honda) +12.929s 5. Jack Kennedy (Colin Appleyard/Macadam Racing) +13.142s Fuchs-Silkolene British Supersport Championship Standings after Mallory Park : 1. James Westmoreland (CAME Yamaha) 81 2. Sam Lowes (GNS Racing Honda) 81 3. Billy McConnell (CAME Yamaha) 79 4. Graeme Gowland (PTR Honda) 54 5. Jack Kennedy (Colin Appleyard/Macadam Racing) 53