Fabio Quartararo Wins at Mugello

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Fabio Quartararo took the win in Mugello, well ahead of the competition. (MotoGP/)

Fabio Quartararo on Yamaha set his fourth pole of 2021 and dazzled us all by winning at Italy’s horsepower-hungry Mugello circuit. Brad Binder’s KTM matched the all-time MotoGP top speed of 362.4 kph (224.7mph), set on Ducati by Johann Zarco. This time, straightaway speed wasn’t enough. Something has changed, as Mugello had been a secure Ducati fortress in 2017, 2018, and 2019 (there was no event here last year).

Francesco Bagnaia (Ducati), leading when he crashed out on lap 2 and the weekend’s only rider at Quartararo’s level, said after qualifying front row, “In the end, the Ducati and the Yamaha are the same on this circuit. We are faster in the first and last sectors and they are faster in the two middle sections—it is a balanced situation.”

Francesco Bagnaia jumped out ahead of the pack but it didn’t last long. He lost the front on the second lap. (MotoGP/)

This is confusing, as no other Yamaha was even close. Maverick Viñales the Unlucky on the other factory Yam finished eighth and Valentino Rossi (Petronas Yamaha) was 10th; they were 17 and 25 seconds out of first, respectively. This hints that at least some of the change is in how Quartararo sets up and uses his Yamaha.

The weekend was darkened by the injury and eventual death of 19-year-old Swiss Moto3 rider Jason Dupasquier, who after crashing was hit by his own bike and then by at least one other. Some proposed that the MotoGP race not be run. Aleix Espargaró (seventh on Aprilia) said, “Today, in the span of 10 minutes we went from honoring him to pulling down our visors.”

Rossi said that a fatality calls life itself into question, but that the tragic event remains the same whether MotoGP runs or does not run. He then said something that recalled important concerns from past Supersport 600 events at Daytona.

“I think the problem is that they are always so close to each other. Especially here at Mugello, where the tow makes a big difference. There are trains of six or seven bikes…”

At Daytona, after years of glorifying “close racing,” the course was changed to make hazardous tight drafting in dense groups less likely to occur.

Asked about Yamaha’s advance to a double holeshot device (which lowers the bike front and rear to enhance starting acceleration) Quartararo said, “Great start thanks to the device. I wanted to take the lead straight away but I had to wait for Pecco’s crash. Then I just thought about pushing and getting away. We don’t have the best top speed [Jack Miller’s Ducati recorded a top speed 7.5 mph faster than Quartararo’s Yamaha], but I don’t think anybody expected to see a Yamaha, a KTM, and a Suzuki on the podium here.” Miguel Oliveira’s KTM was 2.6 seconds back in second, and third-placed Joan Mir’s Suzuki 3 seconds.

At this point it’s interesting to hear a candid view of the developing holeshot technology from Ducati test rider Michele Pirro, sitting in for the injured Jorge Martin. He talked about two corners, the Bucine (last turn) and the San Donato (turn 1 at the end of the very fast straight).

Moto3 Jason Dupasquier died following a qualifying crash, the MotoGP family took a moment of silence before Sunday’s racing. (MotoGP/)

What we must think of here is that at 220 mph an aero drag force of hundreds of pounds is literally trying to blow the machine over backward; engine thrust acts at pavement level but aero drag acts at the much higher centroid of the bike’s frontal area, creating an overturning torque. Yes, downforce from the winglets is intended to counter this, but even so, Aleix Espargaró said this of the straightaway kink and jump over a crest just before the braking point for San Donanto: “It’s one of the most difficult parts of the championship because you are going super, super fast and the shaking of the front wheel is huge. The most important thing is to make the perfect line. I also try to put a bit more load on the front when I arrive there…”

Miller said: “It’s a scary feeling, a fun kind of scary, but you definitely don’t want anything going wrong there. There’s no real technique to it, I just try and grip the bike as hard as I can—I try to pull the handlebars into my chest, to keep the bike as stiff and as straight as possible. I use the curb in the pit lane, so I can hit the brow (crest) straight. That way when you land [!] you can more or less jump straight on the brakes and you haven’t got any lean angle.”

With that intro, here’s Pirro on the holeshot device: “It is very useful especially when exiting the corners but you really become perfectly stable at the San Donato. It’s one thing I really like because three years ago I had a bad time at San Donato.” True; he was thrown into the air there with a locked front wheel at 165 mph, and walked—with a concussion and dislocated arm.

Stability is good, especially at more than 200 mph. Lowering the bike for braking and acceleration reduces the aero overturning torque and so places added stabilizing weight on the front wheel. This suggests that holeshot is quickly evolving into something to be used in several places throughout races, and not just at the start.

Quartararo’s win at Mugello put an end to Ducati’s dominance at the Italian circuit. (MotoGP /)

Now back to the implications of Quartararo’s win and the apparent end of Ducati’s Mugello supremacy. Originally corner speed was the only style in GP racing, as the roughly 50 hp of 1950s and ’60s Norton and G-50 Matchless singles permitted nothing else. When Kenny Roberts brought his dirt-track-originated point-and-shoot style to 500 GP in 1978, it was poorly understood at first. But it made sense for two-stroke motorcycles because it exploited the motorcycle’s strongest suit, acceleration, while minimizing dependence on its weakest ability, which is turning (because bikes have so little footprint area compared to racing cars). Brake late and hard, get turned quickly at a reduced apex speed, then use the rest of the turn to build a high exit speed.

With the later ascendancy of dirt-track-trained riders such as Dani Pedrosa, Casey Stoner, and Marc Márquez, I have considered that corner speed might be effectively finished in MotoGP. Yamaha’s years of poor rear grip in the final laps led to Márquez’s strategy against such corner-speed masters as Jorge Lorenzo: Wait until the heavy tire abuse of using maximum side grip around every long sweeper had so reduced rear grip that Márquez could push past at the very end to win. Yamaha, once so admired for its engineers’ ability to create winning bikes, began to look limited (by an inadequate R&D budget?), unable to come up with anything that could keep the rear tire on the job.

Now Quartararo has accomplished what had looked impossible: breaking the high-horsepower stranglehold on Mugello. After qualifying on pole he said, “That was probably the best lap I have ever done in my life.

“I was on the limit everywhere.”

Second-place finisher Oliveira had good things to say about KTM’s latest chassis: “The goal for the frame was to help us line the bike up a bit better, to get out of the corners better.

“That’s great but more so than that we got some new fuel and that has given us a bit of extra speed.”

What is this new fuel Miguel Oliveira speaks of? (MotoGP/)

That second sentence brings a red warning light on the panel. The fuel specifications that must be met in MotoGP are carefully designed to eliminate the power-boosting dienes added to fuel in the late 1980s and ’90s, with tongue-twister names such as tetrahydromethylcyclopentadiene. All the normal hydrocarbons yield closely the same combustion energy per pound. How, then, could a new fuel give KTM “a bit of extra speed”?

Gasoline for spark-ignition engines is a compromise. If you want a highly volatile fuel that can promptly evaporate to form a fast-burning mixture in a very high-rpm engine, you must rely more on low-molecular-weight hydrocarbon species such as isopentane. But those species do not have the highest resistance to detonation that heavier species such as toluene, the four “good” octane structures, and 1947′s mystery air-racing fuel, triptane, all have.

KTM formerly sourced fuel from Elf, but recently switched to ETS Racing Fuels, another longtime partner. It could be that their previous fuel was slanted toward boosting detonation resistance (high compression, which boosts acceleration, requires the highest detonation resistance) with heavier but less volatile hydrocarbons, and that lower volatility had resulted in less complete fuel evaporation at peak engine revs. It is common in racing that a team focusing on deto resistance unwittingly sacrifices fuel volatility, and even more common that users of race gas in drums notice changes in engine performance in the last third of the drum, after much of the fuel’s volatile “front end” has evaporated.

What can Yamaha and Quartararo have done to revitalize corner speed as a means of getting around race tracks? First point is that Mir is MotoGP champion on Suzuki. That shows it’s not foolish to try—taking winning points with a corner-speed bike can be done, just not recently by Yamaha. Then the question is how design can change or rider technique better protect the tires, not so much from heat as from time-under-strain cycling. Suzuki and/or its riders seem to have found a way to slow the damage that accumulates in the soft, vulnerable tire edges.

Joan Mir seems to have found a way to conserve his tires on the Suzuki. Is it the bike or his riding style? (MotoGP/)

Is this as simple as reducing the motorcycle’s lateral stiffness as a means of limiting peak loads on the tires? Surely not, for early experiments in this direction resulted in instability. This was the outcome of the Honda NSR250 chassis ridden in 1997 by Max Biaggi: as delivered its flex was excessive and it weaved at speed. It was then reinforced back to a stable stiffness level by applied carbon fiber, a practice we are seeing again in MotoGP chassis construction. Speculating further, could it be that Ducati’s “RFD mailbox” seatback is now a tuned mass damper, provided to suppress weave? Or does it suppress chatter? Although unfamiliar to most motorcyclists, dampers tuned to specific frequencies or orders have a long history. Each of the great radial piston engines that powered World War II aircraft carried on their crankshafts two such dampers, one tuned to the cylinder firing interval and the other to second order. We hope for enlightenment.

In the past we saw Márquez and Pedrosa doing the early part of their turning at less-than-maximal lean angle; only as they neared the apex did they drop down to “elbow level” for the phase of most rapid turning. This was a conscious choice—to save the tires.

Have changes in tire design or rubber compounding contributed? All we can hope for at the moment is the little hints that appear in rider comments over time. In a spec tire series, the tire maker must find ways to serve both rider styles.

Barcelona is next weekend. More data!

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