Silverstone’s Tire Conundrums

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Fabio Quartararo increased his point lead with a decisive victory at Silverstone. (MotoGP/)

In winning at Silverstone and increasing his championship point lead to 65, Yamaha factory rider Fabio Quartararo again underlined the chasm that divides those who consistently finish at the front and those who suffer mysterious tire maladies.

Joan Mir (Suzuki), who still holds second in the standings, summed up his day: “I was feeling very strong… But then I started struggling with the front end… and I lost a lot of time in the last laps.”

Mir ran as high as fifth in the race. He finished ninth.

Francesco Bagnaia, regarded by many as Ducati’s Most Likely to Succeed, finished 14th after his medium rear tire deteriorated: “…Something wasn’t working. I felt strong all weekend. In free practice I always lapped with used tire and today I was three seconds a lap slower. I don’t know what happened.

“Quartararo dominated the race with that tire and I had used it all weekend, even in qualifying.

“…The bike was going away from me on corner entry. We have already checked the pressure and it was right.”

Álex Rins found his place on the podium, finishing second on his factory Suzuki. (MotoGP/)

Both Mir and Bagnaia had chosen the soft front—just as Quartararo had.

At the last Silverstone MotoGP (2019) Valentino Rossi’s rear tire had chunked; pieces of tread rubber debonded from the casing and were flung off. This year Rossi said, “After five or six laps the rear tire had an incredible drop—on the right side I had no grip at all.”

Miguel Oliveira, normally strong on KTM, said, “It felt like I didn’t have a lot of grip from the beginning.” He finished 16th.

Jack Miller (Ducati) and Pol Espargaró (Honda) suffered some tire drop but were able to finish fourth and fifth respectively. Miller said, “I struggled a little bit to catch the front group in the last laps because I couldn’t brake in the same way as before.”

Pol Espargaró had led the first four laps using a soft rear (“It gave us the best feeling”), but very slowly fell back. “As the grip dropped I controlled the gap and finished the weekend well.”

Quartararo had performed methodically through practice, evaluating all the tire choices and producing consistent times while topping two practices and being third and fourth in the other two. Pol Espargaró and Bagnaia qualified ahead of him, but Quartararo remained breezily confident, as if MotoGP racing were more like an invigorating hike rather than a grim struggle to hang on to 275 hp.

The opening laps sorted out the field. On the first lap, Marc Márquez (Honda) collided in turn 9 with Jorge Martín (Ducati), putting both men out. Márquez later apologized to Martín, saying, “I went to him and his team to say sorry after the race. It was my mistake. I was too optimistic with that overtake.”

Marc Márquez apologized to Jorge Martín’s team after the race for the first lap crash. (MotoGP/)

Quartararo disposed of the two Espargaró brothers (Aleix on Aprilia) and Bagnaia to take the lead and was shortly 1.3 seconds clear. In the pursuit that followed it was apparent that he had a margin in reserve but was doing the sensible thing, winning at the lowest possible speed. His lap-to-lap consistency revealed he was not making small errors and losing time here and there correcting them.

Near the end there was some special drama as Miller passed Aleix Espargaró for third, threatening to push his Aprilia off its very first podium. Espargaró prepared his riposte well, coming under Miller and thereafter defending successfully against the Ducati’s locomotive power.

Pol Espargaró led the early stages but he had to manage the drop-off of his soft rear tire and faded back to fourth. (MotoGP/)

The order at the end was Quartararo, Rins, Aleix Espargaró, Miller, Pol Espargaró, and the winner of the previous race, Brad Binder (KTM)—a magical six different manufacturers in the top six finishers.

The Current State of Racing

Danilo Petrucci (whose next employment may be a seat in the Dakar Rally) had interesting things to say about how MotoGP has evolved.

“[On the first lap] you can really see the madness of the riders… Now it has become what it used to be on the last lap of the race. Above all, the fact is that at that moment you do not know what the conditions of the bike or the track are. You have a full tank and the tires are not yet perfectly in temperature.

“Before, you used to wait for everything to settle down, and then attack.”

What else can we expect? Experienced, extremely fit and highly motivated young men arrive on the MotoGP grid as rookies, all knowing that they will be mercilessly sent back to the minors if they can’t live up to their billing. What does this tell them? In the words of Linda Ronstadt, Baby, you’re no good. Pitch that bike in there!

When I spoke with Marc Márquez after his first season in MotoGP (in which he became champion), he said, “I rode every lap as if it was qualifying.” We also know that Casey Stoner was mysteriously fast on lap 1, something that all admired but very few could achieve.

What a contrast to the 1920s Isle of Man TT races, when a wise top rider would go easy for two of the seven 37-mile laps to let his engine “bed in,” and then rely upon his pace to carry him to the front over the remaining 190 miles.

Tires and Variable Ride Height

In an interesting development, Suzuki decided not to use its variable ride height system, and Quartararo had difficulty with his. One possibility is that, on this relatively cool weekend (58 degrees Fahrenheit on Sunday), initial tire bite could be marginal with a bike at its low height. Bikes accelerate as fast as they do by transferring essentially all their weight onto the drive wheel; if that transfer isn’t as solid as usual, the tire will spin instead of grip. Same with braking.

Nearly 50 years ago in back-to-back testing, America’s then-premier rider/builder, the late Hurley Wilvert, rode two Kawasaki H2R 750s, his own low-built bike and Randy Hall’s taller machine. He was quicker on the taller bike, and looking for the reason why he concluded that greater transfer promptly put 100 percent of the bike’s weight on the back tire during acceleration. The comforting thing about physics is that it remains true over time and is not subject to news cycles or Facebook voting.

Aleix Espargaró earned Aprilia its first podium since its return to the MotoGP class. (MotoGP/)

Future variable ride height (VRH) systems will surely be automatic (currently forbidden by rule) and their “low” setting will be adjustable for this putative track-temperature effect.

Mysterious Michelins

Moving on to the comments concerning notable tire drops, we see the effects but want to know the cause. Bagnaia’s remarks tell us he suspects he got a bad tire, as he had used the same type (medium rear) through practice without problems.

Rossi seemed resigned: “…Since 2019 this problem has happened to me a lot of times. We have done a lot of tests and made changes both to the setting and riding style.

“After five or six laps the rear tire had an incredible drop, on the right side I had no grip…

“I don’t seem to do anything special. I ride in a similar way to the others.

“We’ll see what we can do but we don’t know which way to turn.”

Valentino Rossi finished 18th, citing a lack of grip from his tires on the right side. (MotoGP/)

Rossi’s Yamaha is not that different from the one on which Quartararo is leading the championship. Rossi was having a better weekend in the four practices (he was 16th, 10th, seventh, and eighth) than he did in the race, where ultimately finished 18th.

Are most riders so inconsistent in the way they use their tires that the rubber’s chemistry can be offended by changes in the manner of use? Quartararo’s consistency is too great to be accounted for by the theory of a “tire lottery.” If there is wide variability in tire quality, Quartararo has taken its measure.

Michelin, known for secrecy, can’t be expected to explain. Piero Taramasso, its MotoGP spokesman, reminded the paddock that Michelin has a massive quality control apparatus behind its tires—yet also noted that rubber is “a living material” in the sense that it is organic.

What we do know is that Michelin rubber has historically worked best in a narrow temperature range. Back when Bridgestone came to prominence, it was observed that because its production was so far from most MotoGP tracks, the company was forced by circumstance to build a wider temperature range into its tires. Such a wider range might be more tolerant of small differences in rider technique.

Is there subtle communication between tires and the most receptive riders? Do tires murmur, “Ow-ow-ow”? Marc Márquez long ago spoke of knowing when to slightly rest a tire that is teetering on the edge of irreversible change. If it is something of this kind that is helping Quartararo, he’s not talking about it.

For more suspense and mystery, tune in on September 12 for MotoGP Aragón.

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