Mat Oxley published an article in Motor Sport Magazine today that reveals how MotoGP teams applied illegal tire pressures.
Front tire pressure in MotoGP is vital because, like Oxley writes in his Motor Sport Magazine articlethe front tire dictates entry, mid-corner and exit speed.
The Michelin front tire has proven to be particularly temperamental since the French brand became the official MotoGP tire supplier in 2016. Throughout its history as a MotoGP tire supplier, Michelin has come under criticism from the from the riders about the front tire one way or another. In some cases, the front tire was criticized for being too low compared to the rear and lacking support under heavy braking; while in other cases it has been criticized for its inconsistency, with many riders complaining over the years of having received faulty tires from Michelin.
In the Paddock Pass podcast after the Spanish Grand Prix, won by Francesco Bagnaia for Ducati, David Emmett said Brembo had seen a 10% year-on-year improvement in braking performance in recent years. Emmett said a more normal improvement is 1% year over year.
This means that more force than ever before is applied to the front tire. This is amplified by the recently introduced rear ride height devices, which not only increase acceleration, but also improve front load under braking. When the rear suspension comes up at the end of a long straight, there is more forward weight transfer than without the rear ride height device. So riders brake later and harder, and weight transfer to the front tire is also harsher than in the past.
As a result, the Michelin front tire – which was due for updates over the past few seasons but those updates were delayed due to the Covid situation and then by supply chain issues – is under increasing pressure.
This increased stress makes it increasingly difficult to get the front tire in the correct temperature and pressure range. Throughout the weekend at Jerez there was talk of the difficulty of overtaking on the Spanish track, with front tire pressure management becoming more difficult behind another driver. Indeed, we saw few overtakes in Andalusia, and Fabio Quartararo spent much of the Bagnaia distance race where his front tire wouldn’t be so badly affected by the hot air coming from the Ducati.
As one rider closes in on another, front tire pressure increases. This had dramatic effects on, in particular, Fabio Quartararo in the past. At Sepang in 2019, Aragon in 2020, and even Aragon last year, Quartararo’s race was conditioned by being behind other drivers, which meant he was unable to handle the temperature and pressure. front tyres, which meant he couldn’t turn the bike.
It therefore makes sense that teams try to reduce front tire pressure as much as possible, not only to increase contact patch and therefore grip, but also to try to minimize the effect of increased tire pressure. .
And how much should a team lower the pressure? The answer is the same as any other competitive engineering question: as much as they can get away with.
The Oxley’s Motor Sport Magazine article reveals that MotoGP teams have a “gentleman’s agreement” with the MSMA and Michelin not to release details of any breaches of tire pressure regulations. These regulations exist to try to ensure that MotoGP tires are not run dangerously low by teams, as too low pressure can lead to tire failure.
It is also shown in the article that Francesco Bagnaia, the winner of the MotoGP race from Jerez, was one of the riders to exert illegal pressure in the race. The regulations state that a rider must not be below the pressure limit for more than 12 laps of a race, but Bagnaia remained below for all 25 laps. Fellow Ducati rider Jorge Martin was under for 24 of 25 laps and, given that he crashed while in the group on lap one, that might not be such a leap to suggest that the lap where he was over the tire pressure limit was the one in which he crashed.
Alex Rins only exceeded the minimum tire pressure for 11 laps. The Suzuki rider lost the front end at turn 11 on lap nine, after which he almost rode alone. After his gravel excursion, Rins’ pace picked up for a few laps, before tire wear started to play a part, and he probably started to realize he wasn’t going to score. dots. Maybe it was only the first 11 laps where Rins’ tire pressure was above the limit, and once he got out of the hot air he started to cool down and the pressure started to drop.
In the end, it’s hard to say, and, as Oxley’s source told him, there’s no way to go back and change the results of old races where the ” gentleman’s agreement” was in place, because you would end up having to reassign race wins, podiums, and championships years after the fact. Therefore, there is also no possibility of penalizing Bagnaia for their victory in Jerez.
However, it is clear that the situation must be resolved. In WorldSBK, riders are randomly selected for a tire pressure check on the grid before each race. Anyone below the minimum limit must go to the pit lane, legalize the pressure and start from the back.
This is a story that is likely to continue until the regulations are properly applied by the FIM. Until they are, it becomes difficult to take everything we see in MotoGP particularly seriously.