Valentino Rossi is eager to understand if the winning form he re-discovered in the recent Assen MotoGP clash carries on into this weekend’s German round at the tight and twisty Sachsenring.
The Italian won a premier class race for the first time since the Sepang race in October, 2010 with a vintage display in Holland that saw him capture an 80th MotoGP victory.
Modifications to the front-end of Rossi’s factory Yamaha YZR-M1 in a recent test at the Motorland Aragon gave the 34-year-old more confidence in hard braking and corner entry in Assen.
Now the nine-times world champion is keen to find out if the Ohlins front fork set-up modifications work around the slower and shorter Sachsenring, which is a completely different challenge to Assen.
Rossi said: “In Assen it was a great weekend and I can stay with the top guys for all the practice in wet and dry and the race was fantastic. Here it will be important to confirm that I have raised my level and increase my speed to try and fight with the top guys. This track is not one of my favourites but I have had some good victories and also in 2010 I have a good memory after coming from the broken leg and doing a good race. We need to understand now if we are in the right way.”
Speaking exclusively to MCN about the critical front-end tweaks that reaped such instant dividends in Assen, Rossi’s crew chief Jerry Burgess said: “We were able to make the first part of the fork stroke stronger without compromising the latter part.
His feeling was the dive speed at that point was too fast and then that inertia loading would go into the casing of the tyre and screw him up on the braking. So we have been able to stiffen the first bit of the stroke up. Not just with the springs but we’ve had to change the internals of the fork too. We’ve had to tune the bike that he left in 2010 to work with these new generation tyres and the softer casing.
So how had the modifications specifically restored a key weapon in Rossi’s riding style?
“It allows him to use his strength for braking while still turning the bike. Before we were having difficulties with the softer construction front and the harder he tried the more mistakes he made, “said Burgess.
The braking and turning issue has never been a complaint of reigning world champion Jorge Lorenzo. But such a difference in riding style means Rossi simply can’t ride the YZR-M1 fast enough when using the Spaniard’s set-up.“We can ride Jorge’s set-up but it is very light on the front and Cal (Crutchlow) follows this way also.
When we try that set-up with Valentino, as soon as he opens the throttle he almost crashes. You need to be very particular with that set-up and it is a little bit too close to the edge and every time we try it he says it is not the bike for him. We have been looking to give him the performance he needs without taking the weight away from the front, “said Burgess.
The problem has been exaggerated on new tyres, which is why Rossi has qualified so dismally all season. Before the new set-up hauled him close to the front row in fourth in Assen, he had only started from the second row once in the other six races.
Qualifying so far back and the new fashion in MotoGP being to go gung-ho from flag-to-flag, Rossi has given himself a mountain to climb to stay in contention in the early laps.
A classic example was the recent Catalunya round when Rossi was fourth. He lost all his time in the opening six laps but after that was frequently marginally faster than Lorenzo, Marc Marquez and Dani Pedrosa.
Burgess said: “Now he can try harder and go faster in qualifying and that was the first hurdle we had to overcome. We had a good rhythm after a few laps but we couldn’t get ourselves to the front of the grid to get started.”
Complaints that the new softer casing is now too soft have been increasing and Burgess believes a move back to a stiffer construction will only benefit Rossi.
The current 1000cc bikes are now capable of top speeds of over 210mph on fast tracks and with 3kg of extra weight to carry for 2013 taking the minimum limit to 160kg,
Burgess said those changes were having an impact because tyre development was minimal with the one tyre rule and no competition to drive improvements and he added: “We now have 1000cc bikes travelling at a lot higher speeds and requiring much higher braking forces to stop them, so as the bikes have developed the tyre development hasn't kept pace as much as it should be.
The tyre situation has been very stagnant other than the supposed safety change and that needs to be looked at it. But we need to look at other things also. As the bike develops like the engine, chassis and brakes well the tyres need to be developed too.
We don’t want to have the bike ahead of the tyres. We’re rather have the tyres better than the bike. I’m not saying there is anything inherently wrong with the tyres but perhaps we need to look at that so we can improve the performance of the bikes for everybody.”