Michelin's return to the MotoGP paddock has been nothing if not eventful. Since taking over from Bridgestone as official tire supplier to MotoGP, Michelin has had both spectacular success and highly visible failure. Lap records (and more importantly to Michelin, race time records) have been broken, but there have also been delaminating tires, compulsory pit stops, and at the start of their time, a lot of crashes as the riders, teams, and Michelin all struggled with the front tire.
It is hardly surprising that the first two years of Michelin's return did not go entirely to plan. Having been out of MotoGP since 2009, it was predictable that Michelin would run into unexpected problems. The spate of front end crashes which marred the first Valencia test was quickly remedied as riders learned to fathom the different nature of the Michelins, teams adapted the geometry of the bikes, and Michelin changed the profile of the front tire to improve the contact patch. The extreme tire wear was dealt with by using harder compounds, which Michelin then slowly adjusted back in search of the right balance.
By the end of their second year in the class, Michelin had a much better understanding of the demands of MotoGP, and tires had become much less of a talking point. That is something of a double-edged sword according to Piero Taramasso, head of Two-Wheel Motorsport for Michelin. "We want people to speak about the tires, but in a good way," Taramasso joked to reporters on the final day of the Qatar test. "But I know this is not the case, I know that when we do well, nobody speaks about the tires, when something goes wrong, everybody speaks about the tires, this is the way it is since forever."
And so the 2018 MotoGP season will mark something of a shift for Michelin. In part as a result of a request from the MotoGP teams and riders, Michelin will be fixing the tires to be used at all races at a meeting this week, instead of a few days before the start of each weekend. The profile and construction of the tires will not change throughout the entire season, with only compounds varying from circuit to circuit.
"The goal for Michelin is clear, it's stability," Taramasso told reporters. "We want to keep stability in terms of tires, so starting at the beginning of the season, we will fix the front casing and the front profile, we will fix the rear casing and the rear profile. This will not change all season. And also for the compounds, 80% of the compounds we will use from last year, plus these two or three new ones which we are validating now." The new compounds were tested at Sepang, Thailand, and Qatar, and will be used this year.
"So teams, riders, they will know the tires very well, because they are very close to what they used last year," Taramasso explained. "We will not change during the season, so they can work on the bike, on the setting, on the engine, without having a problem with tires changing, like we did in the first year."
The rapid development in the first year had upset riders, making it hard for them to get a handle on the tires. "In the first year, we wanted to develop very quickly, to try to give the best tire as soon as possible. And the riders complained, they said, 'The tires change too much, they change the handling,'" Taramasso said.
Changing development focus
Stability in tire development was good for the riders, perhaps, but it posed something of an organizational challenge for Michelin. "The objective this year is stability, but this is because they asked us, the riders and the teams. For us, from a Michelin point of view, we want to develop. This is the reason why we are in MotoGP, because we have 24 riders, the best riders in the world, and we know that in that way, we can develop technology very very quickly, so for us it's better to do."
This has forced Michelin to take a new approach, with development taking place between seasons, based on the lessons learned during the season. Taramasso explained that the rules have been tweaked to handle this. "For this season, we are only allowed for the test session to bring tires for this season. Tires that riders already know. If we want to bring a new solution, new casing, new profile, new compound, we can test during the IRTA tests, but these solutions can only be used for next season, for 2019."
The basic process will be that when Michelin has a new development – a change in construction or profile, or a new compound – then they will first give it to the factory test riders for evaluation. If the test riders like the changes, then Michelin will bring a new tire to one of the official IRTA tests for the contracted riders – riders with a full-time entry in MotoGP – to try out. If the contracted riders like the new tire, it can only be introduced for the following season. "So we are still developing, but slower, and what we validate for this year will be for next year," Taramasso explained.
The one complaint which riders have consistently had about Michelin tires has been that tires that are supposed to be identical (same construction, profile, and compounds) can sometimes feel very different. Riders talk about getting "a bad tire" on which it is impossible to lap at the same pace which the tire is supposed to perform at.
There have been complaints that Michelin's quality control is not always up to scratch. Michelin has countered this by pointing to the fact that there are a lot of things which can affect tire performance, some of which are outside their control. Tire warmers do not always function perfectly consistently; the indicated temperature shown by a tire warmer can sometimes be out by several degrees; tires can be left out of warmers too long, or not go through the proper heat cycle, or even go through too many heat cycles.
Nevertheless, Taramasso acknowledged that quality control was an area which Michelin was focusing on very carefully. "We are still working, it's not easy to understand where this comes from. We need to work, this is our goal. We are working in the factory, in transport, to try to understand [how that affects the tires], and of course, we keep statistics, which we then send to Dorna to prove that we improved compared to last year."
Sometimes, the fault did like with Michelin, Taramasso admitted, as was the case at the Sepang test this year. "So far, we had a small problem in Sepang, but this was just our mistake, because we left some tires from last year's race in the containers at the Sepang circuit, and then we used them at the IRTA test. But probably the temperature in the container had gone up too high, and the tire was not good."
Compounds, compounds, compounds
Taramasso did let slip an interesting detail about the tires when he spoke to the press at Qatar. He was asked how many different compounds Michelin used during the season. "The number exactly, I cannot tell you, because we will decide that next week," the Italian said, though he was willing to give a rough guide. "In the front, we are around 7 front compounds."
The rear tires are more complicated, because so many tires are asymmetric, which use different compounds for the left, right, and middle of the tire. "I would say around 11 or 12 compounds [for the rear]," Taramasso said. "So with that, we are sure to make the right tire for the right condition for the different riding styles and different requirements."
In a way, Taramasso revealing the number of compounds in use is another sign that Michelin are getting pretty comfortable with where they are in terms of development, and the reason they are happy to accept fixing the tires to be used ahead of the start of the season. The number of compounds Michelin are using is pretty close to the number Bridgestone were using during their period as official tire supplier in MotoGP. Michelin are using slightly more front compounds, though this could be a result of their tires being slightly more temperature sensitive than the Bridgestones, and because Michelin are pledged to bring three different options front and rear to each track, rather than the two which Bridgestone tended to.
New surfaces, new tires?
Though the tire compounds are now fixed, there are still a couple of circuits where Michelin are still not entirely certain of the demands which will be placed on the tires. Three circuits have been resurfaced since MotoGP last raced on them: Jerez, Barcelona, and Silverstone.
Michelin already has data from Jerez, after the teams held a private test there in November of last year. But a test will be held at Barcelona before the race weekend in mid-June. Silverstone, which has also been resurfaced, will not see a test, but instead, Michelin will bring four different front and rear tire specifications to ensure they cover all possible options.
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