Yes, Wout van Aert has been winning on rim brakes: so what?

by James Huang


“Eddy Merckx still would have won riding on a singlespeed.”

“Eddy Merckx still would have won riding a Razor scooter.”

“Eddy Merckx still would have won on a tricycle. Backwards.”

So goes the preferred phrase for racing fans that refuse to believe technological advantages play any role whatsoever when it comes to who crosses the line first. Those things don’t pedal themselves, after all, and even I’ll agree that it’s the rider who wins a race, not the bike.

That said, bike racing is still an inseparable marriage of person and machine, and even if the athlete is responsible for 99.5% of the victory, that 0.5% can nevertheless sometimes be the difference between winning and losing.

And so we have the curious case of Wout van Aert and his big wins at Strade Bianche, Milan-San Remo, and the first stage of the Dauphine, riding a Bianchi Oltre XR4 fitted with — the horror — rim brakes.

As you’d expect, the #savetherimbrake crowd has jumped on Van Aert’s wins as proof that rim brakes are still better than disc brakes when it comes to racing, and that when given the choice, a true pro will stay on the tried-and-true, damn the sponsors.

As is often the case, however, it’s not quite that simple. Lighter may be better than heavier, and aero may be better than not, but when the goal is to have the fastest bike possible, there are few absolutes in the business of road racing.

It’s complicated

There’s been no shortage of debate in recent years over the advantages and disadvantages of disc brakes in the road world. Regardless of the fact that rim brakes continue to work just fine for many riders (and yes, I’d agree with that, too), the general consensus remains that disc brakes genuinely work better for average riders, offering more braking power with less hand force, more consistency in varying weather conditions, and better predicability overall. There’s also the safety aspect since you don’t have to worry about rims heating up on long descents.

In the pro ranks, of course, there are other factors at play that aren’t nearly as much of a concern for amateurs.

Despite continuing advancements in technology, disc-brake bikes remain heavier than rim-brake ones in many cases (particularly in terms of rotating weight). Given the tight rotor-to-pad clearances, they’re more prone to rubbing and require more care in setup, which is why we’re seeing more complete bike changes recently during races instead of just front or rear wheels when a rider gets a puncture. Given the outsized role of aerodynamic efficiency these days, it’s also worth noting that disc-brake bikes are also less aerodynamic than many of their rim-brake counterparts.

And so it would seem obvious that any discerning professional racer with an interest in winning would go with the rim-brake bike if given the choice, no? And, clearly, Van Aert’s decision to run rim brakes is an indication that pro riders are only running disc brakes because their sponsors are forcing them to, right?

Maybe. Or maybe not.

I posed the question of whether top-tier pros actually like disc brakes to a close industry friend of mine with intimate knowledge on the subject (who preferred to remain unnamed). The answer?

“Yes and no. Many love them. It’s a new-school-old-school thing. But they’ve also been forced to wear helmets long before it was mandatory. Same with indexing and clipless pedals.”

Maybe – just maybe – Wout van Aert is just such a good bike handler that he would have reeled in Julian Alaphilippe on the descent off the Poggio regardless of what brakes were on his bike? Photo: Anton Vos/Cor Vos.

Van Aert may fit more in that “new school” demographic in terms of age, but he’s also a cyclocross racer at heart, and a Belgian one at that, with a recorded history of flip-flopping between disc brakes and rim brakes. Does he prefer one over the other? I haven’t had the chance to ask him that question myself so I can’t say, but it seems pretty clear that he’s open to whichever setup he thinks will give him the best chance of victory on any particular day.

A question of marginal gains

Ah, yes, that lovely phrase popularized by Dave Brailsford in the Team Sky days that referenced the squad’s unending drive toward eking out every possible advantage, however small they might seem.

Brailsford may have brought the idea into the public eye, but Silca owner Josh Poertner embraced the concept far earlier, dating back to his days as the technical director at Zipp when the company was working closely with Bjarne Riis and Team CSC. Poertner is such a big believer in the idea that his podcast is even entitled, “Marginal Gains“.

“It’s really the aggregation of marginal gains that makes this work,” he said in the initial episode. “You see it in the data. It’s all of those things adding up in time. And when you get the perfect rider in there for the perfect situation, the opportunity to win is significantly improved. It’s the hidden advantage. Over time, the numbers work in your favor.”

When viewed through the lens of marginal gains, Julian Alaphilippe should have had more cards stacked in his favor at Milan-San Remo. His Specialized S-Works Venge was certainly more aerodynamic than Van Aert’s Bianchi Oltre XR4, and those hydraulic disc brakes should have given him a theoretical edge on the descent off the Poggio as the duo raced toward the finish.

Despite Van Aert’s rim brakes, Alaphilippe’s much newer bike may have have still been lighter, which would have helped him pull away as he went up the Poggio. A production S-Works Venge I have here with a similar (but not quite identical) build tips the scales at 7.3 kg with pedals. I believe Alaphilippe’s machine was fitted with tubulars instead of my production bike’s clinchers, too, which would have brought the weight of the complete bike closer to the 7 kg mark.

And yet Van Aert reeled in Alaphilippe on the descent, and even though aerodynamics play an outsized role at the higher speeds the pair would have achieved in that final sprint, it was the Belgian who pulled ahead by half a wheel.

Surely all that marginal gains stuff is hogwash, right? See, it’s once again only the rider that matters, and rim brakes really still are better, right???

Deceuninck-Quickstep 2020 team bike Specialized Venge Sam Bennett
From an aerodynamics standpoint, there’s likely a pretty decent gap between the latest Specialized S-Works Venge and a Bianchi Oltre XR4. Photo: Dave Rome.

Sorry, folks, that’s not how this sort of thing works, and even Poertner admits that when it comes to the chaotic nature of road racing, the whole concept of marginal gains is more a matter of probability and statistics, not clear predictions of who will win and who will lose.

“In a time trial or hour record or Everesting, we can do the math and get damned close to the final number,” Poertner told me when I called him earlier today. “But you can’t do that in a road race because there are 10 million other factors — particularly, everyone else.”

Critical mass

Here’s the thing about the argument that rim brakes are better because Van Aert used them to win a bunch of big races: it’s hollow. And while Poertner readily acknowledges that marginal gains aren’t everything, there are reasons why so many teams and riders pursue them with such zeal. It’s a game of numbers and opportunities.

“When you think of it from a bifurcation point of view, when does the critical move go? And in that moment, what are the limitations? If you’ve got the weight advantage for a given amount of power over the other rider, you’re putting them into a deficit. That’s potentially the marginal gain that opens that gap.”

Rim brake advocates — and anyone who looks down on the performance gains of technology — have been saying for some time now that it’s the riders that win bike races, not the bikes. To that effect, aero bikes don’t matter, aero wheels don’t matter, nor do ceramic bearings, special chain treatments, team-issued mattresses, fancy nutritional supplements, and so on.

Yet by that same argument, the fact that Van Aert won Strade Bianche and Milan-San Remo doesn’t counter the idea that technology plays a factor. If anything, it might even reinforce it.

In my opinion, Van Aert most likely went with rim brakes not because they’re better than disc brakes, but because he would have been at a distinct disadvantage otherwise. Jumbo-Visma’s Bianchi Oltre XR4 is a fine bicycle in its own right, but it’s hardly competitive with more modern machinery on the technology front.

Jumbo-Visma 2020 team bike Bianchi Oltre XR4
Jumbo-Visma’s Bianchi Oltre XR4 bikes are beautiful, but they’re also not as light as others in the peloton. Photo: Dave Rome.

In terms of weight, the Oltre XR4 isn’t far off from the Venge, but that’s only in rim-brake form. Production disc-brake Oltre XR4 bikes with similar components to what Jumbo-Visma uses regularly come in nearly a full kilo over the UCI limit. And that limit is the key. Without any restrictions in place, for sure any racer would go with the lighter bike, all else being equal. If Specialized actually made a rim-brake Venge that was just as stiff, just as aerodynamic, and substantially lighter, you know damn well Alaphilippe would want to use that on any kind of climbing-intensive course if he could.

But he can’t.

Again, the goal these days isn’t to have the lightest bike; it’s to have the fastest bike that’s as close as possible to 6.8 kg, all in. And the harsh reality is that some companies have done a better job of that than others.

“Absolutely, the equipment [Jumbo-Visma] have got — they’re on heavy bikes,” Poertner said. “You know the better-funded teams with equipment advantages are at 6.805 kg.”

Jumbo-Visma is hardly unaware of this disparity, either.

The team has been open about occasionally running Corima front wheels in certain events because they’re appreciably lighter than what they get from their main component sponsor, Shimano, and they even go so far as to race on unpainted framesets in the big mountains to save a few dozen grams.

See those front wheels on the bikes of Jumbo-Visma? They sure aren’t Shimanos. Photo: Tim van Wichelen/Cor Vos

Similarly, Ineos — no longer Sky, but still the team of marginal gains (to go along with its massive budget) — knows that their fancy Pinarellos are heavier than many other bikes, and so they switched to ultra-feathery Lightweight wheels in key stages of last year’s Tour de France despite their well-publicized aerodynamic drawbacks.

As such, I’d argue that in choosing rim brakes over disc brakes, Van Aert wasn’t championing the clear technological superiority of the format, but rather was just using them as a way to lessen the technology disadvantage in another area (weight, in this case) so he could have a better chance of winning.

When he soloed to victory in Piazza del Campo at Strade Bianche, it wasn’t because he had rim brakes, but the reduced weight almost certainly left him with a little more gas in the tank over that lumpy parcours such that no one could follow him when it mattered most. And when he outsprinted Alaphilippe on the Via Roma, it wasn’t because his rim brake pads were rubbing less, but it may have been because ditching that few hundred grams saved him a few seconds of chasing back on over the top of the Poggio and left him with a hint more kick in his legs after more than 300 km of hard racing.

In other words, just like disc brakes don’t win races and aerodynamics don’t win races, it wasn’t the rim brakes that won Strade Bianche and Milan-San Remo. Wout did that. But tossing off some excess ballast probably didn’t exactly hurt, either.

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