Milk, Cream, and Grip

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Aleix Espargaró won the first MotoGP race of his career at this weekend’s Argentina Grand Prix, riding for Aprilia. The victory also gives Aprilia its maiden win in the premier class (in the new GP era). (MotoGP.com/)

At the Sepang preseason test, rider Aleix Espargaró and others had glowing comments about his new Aprilia’s turning ability. An Aprilia win was predicted—the manufacturer’s first—and now here it is.

Due to late-arriving air freight (“supply-chain problems”?), there was just one day of practice, yet Aleix Espargaró took the pole position and looked the part. At the start, Jorge Martín set the pace with Espargaró just behind, the pair quickly gapping the field.

Martín said, “From the first laps I felt that he’d pass me sooner or later, and that’s what happened four laps from the end, despite having tried several times to push him to make mistakes, which he didn’t make.” Pushing a rival in hope of provoking a mistake is a common race strategy.

On the last laps the leaders were very close, with Álex Rins (Suzuki) just 0.8 second behind Martín. Having run wide twice on lap 10, Espargaró seemed to refocus himself and worked to apply his advantage, rebounding with a disciplined push and, on lap 15, setting the fastest lap of the race. He led to the flag.

Let’s remember Aleix’s enthusiasm for the 2022 Aprilia at Sepang: “You can carry as much speed as you want. It’s unbelievable how much the bike turns.

“But I’m limited by the chattering. Even in our fast laps, Maverick [Viñales] and myself have to close the throttle a bit and enter into the corner slower to avoid the vibration, but not because [otherwise] I will go wide.”

Espargaro’s daring pass of Pramac-Ducati’s Jorge Martín on turn 5 in the 18th lap secured his place at the top of the podium. (MotoGP.com/)

All About Grip

This made me remember a long-ago conversation at Daytona with English rider Mick Grant, who noted, “Chatter occurs most under conditions of high grip.”

Yet this same weekend, there was Michelin’s “proclaimer of good times,” Piero Taramasso, describing “…this low-grip Termas track surface.” And here was last year’s champion, Fabio Quartararo, speaking of his Yamaha’s usual reason for uncompetitiveness—low grip.

“The big issue was rear grip and top speed,” Quartararo said. “We already knew about the top speed but the rear grip was ridiculous.

“I was losing positions [he dropped from a second-row start to 13th in the opening laps] and seeing other guys pull away in places like turn 6, which is just a matter of picking up the bike and opening the throttle. Pure grip. It was really frustrating, and the first laps were a nightmare.”

Then, he commented, the track “rubbered-up,” grip improved, and he was able to “recover” to eighth, 10 seconds out of first.

Taramasso also noted again the closeness of competition. Despite losing a full day of practice, there were 19 riders in the first second after the first free practice, and six manufacturers represented in the top six spots. Riders have often commented, “Blink at the wrong instant and you lose ten places in qualifying,” but it’s just as true in the races themselves—ride a bike that doesn’t quite suit the conditions and you find yourself downfield.

Pramac’s Martín’s and Suzuki’s Álex Rins’ second and third place finishes, respectively, made for an all-Spanish podium. Nine different riders have been on the podium over the first three races of the season. (MotoGP.com/)

Suspension and Grip

This deserves some examination. Years ago I learned something valuable from a friend who raced a Vincent 500 single in vintage events. In stock condition, that bike’s girder fork linkage is strongly anti-dive (a “religion” of sorts that attracted many believers in GP racing and US Superbike circa 1980). The effect on the Vincent is so strong that race-level braking tops the fork hard against its stop, effectively immobilizing the suspension at full extension. When that occurs, the wheel can’t follow the pavement’s profile, causing the front tire to slide, greatly extending braking distance. With new fork links that eliminated the anti-dive, much stronger braking became immediately possible.

We know from conversations with many riders that MotoGP bikes and their tires are made very stiff: when cornering at over 2G, to have any suspension travel left springs and tires must be stiff. Compression damping conspires with the rest to make creating and maintaining grip very sensitive. Here we have these several forces, plus the lateral stiffness of the bike’s steering head and swingarm, and must nevertheless compromise with the need for some degree of tire motion. This is a case of very small setup changes having large effects on grip. How many times have we heard the winners of earlier GPs trying to make sense out of mysteriously having no grip once the race starts? A bad tire? A temperature change? Humidity affecting the surface?

And yet, once a rider wins a race, 50 microphones are thrust into his face with the same pointless and unanswerable question—”Does this mean you are now a contender for this year’s championship?”

Eddie Lawson complained in his first year of 500cc GP racing (on the leaping, shaking two-strokes) that after he’d spend practice persuading Yamaha mechanics to firm up the suspension so he could launch rapid maneuvers, at the next event his bike had reverted to the soft settings which returned the molasses-like steering response of a 1948 Buick.

Real-World Reality Check

This reminds me of something materials researchers pondered in the 1920s: Based purely on the mutual attractions of metal atoms for each other, metals should be far stronger than we find them to actually be. I suspect something similar is at work with tire traction. Using lab equipment, technicians measure extremely high values of rubber grip against pavement, but out in the contaminated, bumpy, and impure real world, much less actual grip can be realized.

Argentina is just a single data point, and it remains to be seen whether Aprilia has indeed discovered something new. Meanwhile, Aleix Espargaró has also observed that just having the wonderful grip that the 2022 bike displays isn’t enough. At the Sepang test he said, “I don’t think we are in a great position—because of my riding style. I’m very fast off the brakes. I can do very high speeds in the corner, but when you follow [a] Ducati you cannot do this style.

“Even behind a Honda or KTM you cannot. They stop you in the middle of the corner because their bikes are not turning like us, and then they use the extra power they have [to accelerate away].

“So I’m forced to do more stop-and-go style. I’m not good at the stop-and-go riding style, but I think Aprilia is not good [at it].

“If I don’t start from pole position, then it’s going to be difficult.”

This time, that’s just what he did do—start from the pole—and he won.

Drawing the Line

Why ride on the same line as the others? Because often that’s the only clean line with grip. Jack Miller (factory Ducati) commented, “There’s a couple of bumps going into turn 1, and there’s the clean line and the dirty line. I wasn’t able to put a wheel into the dirty line. If I did, I’d instantly start to lock the front wheel or have moments.”

Miller is a strong rider, so where was he? “I…had to ride a very clean, tidy race and try not to go out of the line at all. I wasn’t able to force in the braking zones as I normally can. I wasn’t able to use the front like I normally would.”

Because he had no confidence in the front, he was unable to make a single pass in the race, and consequently finished 14th.

Francesco Bagnaia had a different experience. “We did a really good job in the warmup, and we were lucky it was extended to 40 minutes.” (Normally Sunday-morning warmup is just a 20-minute run, but it was doubled due to the loss of Friday practice.)

Bagnaia continued, “I regained that confidence in the front that I was missing. In the race I was able to push under braking and cornering. I needed a race like this.”

He finished fifth, behind the two consistent Suzukis of Rins and Joan Mir.

Why can’t teams relay their data to their factories, where intensively developed vehicle-dynamics math models spit out killer settings? It appears that at least for the moment, those models exist mainly to enable their creators to attend the usual international symposia, and to publish learned papers.

Another example of a strong rider restrained by elusive grip? Enea Bastianini. “The problem was the rear. At certain times I couldn’t stay in. As soon as I did a bit extra, I couldn’t keep my rear [tire] in line.”

How about Miguel Oliveira, who won in Indonesia but was 13th at the finish? “We had very low grip levels…”

Or the Hondas, so strong in preseason testing? Takaaki Nakagami, 12th: “During the race I dropped positions and I couldn’t recover them. It was difficult, as I couldn’t keep my pace.”

Pol Espargaró: “We had an up-and-down weekend but we made a good step in qualifying and then we were putting together a good race.… Then a few laps later I fell at turn 2. I was pushing very hard to improve.” (He was in the front group at the time.)

Álex Márquez, 15th? “…in the first corner I got touched by another rider, which lost me some places. In the race I didn’t feel confident or good, so I struggled.”

Marc Márquez did not start, owing to continuing vision troubles.

Somehow manage a good setting and you’re up front—otherwise you may have nothing to work with. All that horsepower with no reliable connection to the asphalt.

Espargaró leads the standings with a seven-point advantage over Red Bull KTM Factory Racing’s Brad Binder. Just 25 points separate the top 10 riders. (MotoGP.com/)

Hoping for Normal

Riders are still hoping for an early return to something they call “normal.” Bagnaia said “I think that when things get back to normal we will see more consistency in the results, perhaps starting with Austin.”

When things are “normal,” top riders rise like cream to the front, and upset wins by the milk cease. Consistency regains its value. God is in His Heaven and all’s right with the world.

Meanwhile, there is discussion (just as there was here in the US a number of years ago) over the possibility of saving time and money by switching to two-day MotoGPs.

After just three of 21 rounds, it’s far too early for meaningful consideration of a possible champion, but Aleix Espargaró now leads Brad Binder (KTM).

The Austin, Texas, MotoGP at Circuit of The Americas is next weekend.

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