There has been a lot of talk of tires in 2021. Tires are always a key part of the performance package in motorcycle racing, but they seem to have played an even more important role in 2021. At Silverstone, Pecco Bagnaia complained of a bad rear tire, while Joan Mir said his front tire was off. Two weeks later, it was the turn of Fabio Quartararo to complain of his rear tire, and there have been a litany of complaints from riders throughout this season.
Are these complaints justified? From outside, it is hard to tell. With grids commonly separated by a second, and grid rows separated by a tenth or less, the differences between being perfect and being just slightly off in terms of setup, tire pressure, bike balance have grown massively in importance.
This is not made any easier by the fact that the Michelins have a relatively narrow operating window in terms of temperature. Go just outside that temperature range, and performance drops off dramatically. The devil is increasingly in the detail, and tires are the biggest detail of all.
The benefits of racing
But Michelin are here to stay in MotoGP. The French tire manufacturer recently extended their contract for another three years, through the 2026 season, a clear sign that they see value in being the official tire supplier, despite the fact that this exposes them to so much criticism.
Michelin's Two-Wheel Motorsport Manager Piero Taramasso gave a bit of background on the contract extension. "We are happy about what we did in MotoGP, what we are doing, and it's still a good platform to develop, the tires, new solutions," the Italian boss of the French tire maker said. "We have a very good collaboration with the teams, with Dorna, with the riders. So that's why we decided to stay."
In addition to using MotoGP as a development platform for their tire technology, it was also a great showcase for Michelin, especially thanks to the series producing close and exciting racing. "Also what we like is the show," Taramasso told me. "The races are very nice lately, there is a fight. So we want to stay. This is the main reason."
I also asked about the seeming increase in the number of complaints of inconsistency from one tire to another this year, whether the supply chain issues seen around the world this year had affected their production process, or whether the Covid-19 pandemic had otherwise affected the way they produced tires. Taramasso insisted they had not.
"It's just a combination of factors, I think," Taramasso told me. "We didn't change the way we build the tires, we still build the tires in the same place in France, we use the same material, we use the same compound, the same casing."
Nor had Michelin changed anything once the tires got to the track either. "We didn't change the way we work on the track. When we move the tires, they are always with the air conditioning, so we didn't change since last year."
Taramasso acknowledged that more riders had complained of inconsistency, but he put it down to just how tight the field is in MotoGP at the moment. "It's true that this season there are more complaints. Like you see, the level is very high, there are always 15, 20 riders in one second, so if you are two tenths slower, you are at the back of the grid, if you are two tenths quicker you are in the top five. So everything is more extreme, I would say."
Figuring out exactly what is causing the loss of those two tenths from the tire can be incredibly complex. "There are many many factors that can contribute if the tire is one or two tenths slower. It depends on the track temperature, the pressure, many many things," Taramasso said.
With time after the race to comb through the data, Michelin and the teams were usually able to figure out a reason for a particular tire not performing as expected, the one exception being Pecco Bagnaia's rear tire at Silverstone. "All the complaints we had lately, the only one that we are still investigating is Pecco's tire in Silverstone. The other complaints, we analyzed with the teams, and we agreed that there is nothing about tires. I don't know if you saw Fabio's declarations yesterday. After Aragon, Fabio said, 'yeah, the rear tire this and that,' and then when we analyzed the data, it's not the rear tire. This is what happened in 99% of the cases."
The reason riders were so quick to point to the tires was the fact that they are the most important component on the bike, Taramasso pointed out. The tires are the single point of contact between the bike and the asphalt, between the rider's brain and the track surface.
"Everything goes through the tires, all the feeling from the riders, when they brake, when they accelerate, when they lean the bike, everything they feel it comes through the tire," Taramasso said. "So the first reaction is 'ah, the tire is bad', but it's not. I understand the riders, because this is what they feel, but the reason is not because the tire is faulty, or we have a problem with the tire."
With the competition on a knife edge, and every detail counting, then pointing the finger of blame at the tires was understandable. "But I understand it's very tight, so now, two or three tenths is very very vital, it's very very important, because everything is pushed to the extreme, the tire, the aerodynamics, the engine, everything."
Getting it just so
The Michelins seem to be exceptionally sensitive to both tire pressure and temperature. Teams have certainly started paying more attention to temperature and pressure during the race over the past three or four years. Tire valves are now fitted with temperature sensors as standard, as well as pressure sensors, with some teams even investing in infrared sensors which measure the temperature of the inside of the carcass, in addition to the IR sensors on the mudguards and swingarms. Riders have lights warning them of rising pressures on the dash, something which was a rarity back in 2017.
But Piero Taramasso counters this by pointing out that tire pressures and temperatures have always been a critical part of racing. "It's always been like this," the Michelin manager told me. "We know that, especially when you follow some riders, the front temperature goes up, the pressure goes up, so you overheat the tires, you lose grip, but it has been like this all the time."
Compared to 2020, the tires are usually the same spec, so the increase in complaints can't be related to tire construction. "We didn't change anything about the tires, they are exactly the same, compounds, and the places we have been. So it was the case also before. And now they are more sensitive, because when it happens, you lose places and it's a big step."
One complicating factor for Michelin is the fact that they are forced to submit the choice of tire compounds and constructions to be used for every race on the calendar of a particular season before the first race even starts. This was an explicit request by the teams and factories, to allow them to prepare better for the races ahead of time.
It has a major downside, however. It means that Michelin have to take their best guess at what the weather at, say, Silverstone in late August might be. England's fickle summers can mean it could be 14 degrees and overcast, or a bright and sunny 30 degrees, or anything in between. Michelin's tires have always been at their best inside a slightly narrower temperature range, so getting the allocation right was always difficult.
"It doesn't help us to choose the tire in February for August, September, October, because you cannot anticipate the weather conditions. So it would be better for us to change, but this is the rules, we try to adapt," Taramasso said.
For 2022, Michelin would be refining its allocation to remove the compounds that work at the extremes, and focus on making their existing tires work over a wider range of temperatures. "For next year what we might try to do is to make a simple tire range, maybe take out the extreme tire, just keep the compounds that work with a temperature range. So that might make it easy for riders to pick the tire, and maybe makes more homogenous the feedback," Taramasso explained, adding that this is exactly the kind of technology and data which can be transferred directly to their street tires.
The one complaint which Honda and KTM in particular have is the lack of support from the front Michelin. The tire is not as rigid as some riding styles, such as that of Marc Marquez or Brad Binder, demand. After a couple of initial tests in 2019, Michelin had originally planned to test a new hard casing in 2020, with a view to introducing it for the 2021 season. But the Covid-19 pandemic put paid to that plan, and Michelin have been forced to push the introduction of the new spec several years.
"The Covid situation slowed down development, so we still need to do more tests. But we are still working on that, on a new front solution, a new front casing," Piero Taramasso explained. The delay did allow them to also try to reduce the effect of following other riders and riding in a group. "What we will add, because we know that the front temperature goes up when the bikes follow other riders, so we also have this objective with the new front casing. So we will try to solve or at least reduce this problem."
This development, and the limited amount of testing which MotoGP does now, means that Michelin have had to push back the introduction even further. Especially given just how important the front tire is: the front is what the rider feels in their hands, what they use to chase corner speed, how they judge the limit on braking. "If I have to tell you something, I suppose we will be able to test the tire in 2022 and 2023, to be introduced maybe in 2024. This is a realistic plan. Because the front tire, because it's the feeling of the rider, you need much more time to validate it than the rear solution," Taramasso said.
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