Eddy Merckx says having disc brakes in the peloton is 'irresponsible' and 'life-threatening' in an interview with Sporza


Cycling legend Eddy Merckx believes that having disc brakes in the professional peloton is ‘irresponsible’ and ‘life-threatening’ in the wake injuries reportedly caused by them at Paris-Roubaix.

Movistar’s Fran Ventoso suffered a deep cut to his lower left leg in the cobbled Classic on May 10, which he said was caused by one of the 16 disc brake-equipped bikes in the peloton.

Subsequently, the UCI suspended its testing of disc brakes and Merckx agrees with the decision to remove them from the peloton.

“Having disc brakes in the peloton is irresponsible, it’s even life-threatening,” he told Sporza. “The only advantage you have is when it rains. But with a disc brake your wheel is heavier and it’s more dangerous.”

Several riders have spoken out about the dangers of disc brakes, including Ventoso in an open letter after his accident.

“Disc brakes should have NEVER arrived into the peloton, not at least as we know them right now,” Ventoso wrote.

“I haven’t met any rider who has run out of braking power with traditional brakes; I haven’t known anyone who didn’t see his wheels skidding when you brake with all power you’ve got, no matter traditional or disc brakes. Then: why using them?”

  • Patrick Storey

    Sorry, I should have known better…

    Of course, the problem with a shroud is it might add an unacceptable gram or 3 to the weight of the bike. Can’t have that.

  • PavePusher

    Yeah, and helmets were considered to be dangerous too…..

    I swear, cyclists are utterly schizo about technology.

  • PavePusher

    Or a shroud…

    Now stop being reasonable, that’s not allowed with bike-racing technology.

  • Patrick Storey

    Personally, I’m not a DB user, but couldn’t this be solved by simply radiusing the outside edge of the disc instead of leaving it square-cut?

  • West Ham, Egg and Chips

    To be honest, i see no issue with them on bikes used by you and me. I can fully understand why the Peloton don’t want them in there though. I suspect they’ll become a bit keener when they can change a wheel as quickly as they can with rim brakes. From what i gather the use of DBs makes getting a wheel from neutral service trickier as well.

    I think this is one of those things where what’s good for the Professional Peloton =/= Leisure riders and vice versa.

  • West Ham, Egg and Chips

    Not even then. The bike could come to a standstill, but the wheel could easily still be turning round.

  • Stevo

    More to the point is rhe facr that a chain ring stops moving the instant you stop pedalling. A brake disc will keep sawing away until the bike comes to a standstill.

  • Sam Hocking

    Just look back at all the famous big crashes from the last 50 years and the overwhelming cause of them is lack of grip of the front wheel, the rear/front wheel locking up under panic braking, or simply the fact that a human body crashing in front of you will always stop faster on tarmac than any brake and tyre can offer and no matter what braking system you use, you will crash into them and then probably crash yourself.
    I would say anti-locking brakes is much more of a priority on a road bike. Disc brakes I love on an MTB and Cross Bike because the knobbly tyres have grip to use it, the stays and forks don’t get clogged up with mud and the braking works when the wheel is half under water too. None of this is an issue riding a road bike in the peloton.

  • Chris Coulter

    I can’t remember exactly where I saw it, but it came from an interview with Wayne Lumpkin (founder of Avid brakes). He gives a very similar explanation which I found intriguing. I want to see it for myself, so I did the math. The rest is really quite simple physics regarding the mechanical advantage of levers – Stephen B’s sparkling retort aside…

    Of course, the *theory* is dependent on a lot of factors that may (will) change in application – and these are without even touching on the subject of heat dissipation:
    1) Is the kinetic coefficient of friction at the braking surface the same in both systems?
    2) What are the differences in friction in the force transmission for each system?
    3) How much loss of force is there in material flex (calipers, pads, housings, etc.)?
    4) What are the differences in mechanical advantage in the linkages outside of the wheel/rotor. Specifically, what is the difference in force multiplication through the hydraulic system versus the force multiplication of the levers moving and being moved by the cable. Our muscles lose fine control the harder we use them, so if there is not enough advantage built into the hydro system, real-world modulation will suffer. Which leads to…
    5) What level of control does the user have? We are not robots, and while one rider may be able to ramp up the force applied in increments of 0.5kgf (4.9kgf) where another user might only be able to apply force in increments of 1kgf.

    Which is all just a long way of repeating this, “It can be argued whether or not extant disc and rim calipers have equivalent fine control within those ranges”

    But again, the physics is clear on the topic of the relationship between disc diameter and available modulation.

  • knobularlife

    Good Point. I am being selfish and really only want disk brakes for my wet weather rides. Drives me nuts knowing that my rim brakes grind down my sweet hoops 🙂 Sorry Eddy for calling you “old”

  • West Ham, Egg and Chips

    Yup, but in a high speed crash in the peloton the chainring is likely to have the chain on it stopping it from slicing anyone. If there’s a group crash and all the riders are in the small ring, they’re not likely to be going that fast. There’s nothing to protect a fast spinning DB in a high speed crash though.

  • Chris Coulter

    I used kilograms rather than kgf or newtons to simplify the discussion for the layman. If you would care to substantively refute either my math or my physics, I would love to learn where I went wrong so I can correct my thinking. However, since you claim to have stopped reading after the first paragraph, I will not hold my breath.

  • ummm…

    motorbikes are for race organizers and media. I think they need to look at the safety protocol, but they are essential if the sport is to exist in the way it does now. Of course we should always be suspicious of pro cycling and some industry trends because of their history of deceit. However, to compare motorbikes to DBs is not compelling, for me. This would be a truly strange conspiracy to have hatched. Do you have a reason has to why there would be such organized deceit? The equipment trend is towards road DBs, the riders have expressed that in the wet they may be slightly better, this is NOT the first year that they have been in the peloton; so why would the UCI and co conspirators go through such a great length the roll it back? I’m not against allowing for conspiracy, but what is the compelling evidence or hypothetical?

  • The Awakening

    RE: “Eddy Merckx says having disc brakes in the peloton is ‘irresponsible’ and ‘life-threatening’…”

    Well done to Eddy Merckx for making that statement.

  • Chris

    Chris, Can I pick you up on the following statement “modulation is inversely proportional to the diameter of the braking surface”. Since your calculations are wholly based on this theory, it would be nice to know whence it came. I am not disputing it, but given my many years in cycling, I’m surprised I have never heard of it. I would be grateful if you could give me the reference you used.

  • Jay

    That’s the point. Everyone is taking their story at face value and I think their decision making is extremely haste and sketchy, and ill informed. Compared with riders incidents with motorbikes you would think they should act on this with greater speed and exigency.

  • ummm…

    yes, it appears we can land on mars, or a passing asteroid. However, strangely enough can’t figure this out; unless you consider their actions to remove DB from the peloton and speak out against their safety indicative of the due diligence even the most inept of international sporting bodies are capable of. This would be a truly elaborate ruse from the rider, and “allegedly” the second injured rider, for the purposes that are yet unclear – if they exist at all. This is to say, why would you not take this story at face value and believe that there was a likely implementation error with DBs (that can be corrected) and may have caused an injury to one or more riders. Why assume that the rider is lying? Why assume that the UCI has acted to fix an ill that was fabricated for some unknown gain?

  • Jay

    So far no one is certain what caused Ventoso’s injury so UCI made a decision purely on speculation.

  • ummm…

    what does this mean; “the nature of the injury isn’t conclusive evidence to ban further testing”?

  • Jay

    As you probably know, there have been a few articles in the media trying to assess Ventoso’s wound and he also wasn’t exactly sure himself. I am not disc bias but I just think the nature of the injury isn’t conclusive evidence to ban further testing. Again one beg the question does it take for a rider to properly get sliced by a disc rotor with formal medical diagnosis for UCI to ban discs. This will be a difficult question to answer.

  • ummm…

    and how do you figure that? I’ve seen a sausage cut cleanly with a disc brake. Look at it on GCN. Your argument is absolutely ridiculous.

  • ummm…

    nobody said that they dont. but the implementation was flawed. Why do you doubt that the rider was injured by disc brakes? why is that so hard for you to believe? What could such an injury have been? Why would the UCI react in such a way if the “allegations” were unfounded?

  • Jay

    Any changes to bike components may carry the inherent risk of crashes whether the injury is directly related to the component. If the rider was actually injured by the disc rotors then granted the component is unsafe. UCI’s problem was they failed to investigate thoroughly before making this decision. It may seem cruel that riders needs to suffer in order for the UCI to make an informed decision but this is all about trials and tests, and it seems there are hardly any data to suggest discs does not belong in the peloton.

  • Rob King

    A more accurate comparison is the disc is a butter knife and the chainring is a steak knife. I know which one I’d rather come in contact with.

  • ummm…

    its the diff between a butter knife and a katana.

  • ummm…

    there is a need for them for 2 reasons in the least; pro cycling needs some drama to deflect from all the other pathetic problems, the cycling industry needs us to by more overpriced dreck.

  • ummm…

    false comparison. downtube shifters dont cut people. lets say this rider actually got cut by the DB (which for some strange reason can’t be substantiated) what then?

  • Aaron Paterson

    Hey we’re not in May yet. Please fix the typo above. Paris – Roubaix. was in April.


  • knobularlife

    Too much sauce old man. That chainring can hurt you also.

  • Chris Coulter

    It’s a common misconception that rim caliper brakes provide better modulation. In fact, modulation is inversely proportional to the diameter of the braking surface. For example, let’s say we require 100kg of force to lock-up a wheel in a given situation. Let’s also assume that we have the same coefficient of friction for both rim and disc brakes at the braking surface.

    If we then say that the radius of the wheel is 370mm (350 for the rim and 20 for the tire) and the caliper brake applies force at the rim, the mechanical advantage of the caliper brake is 350/370 = .946 which means that to apply the necessary 100kg of force to lock-up the wheel, the rim caliper must apply 105.7kg of force. Now consider a 140mm disc brake on the same wheel. The advantage of this lever is 70/370 = .189 which mean that the disc brake caliper must apply 528.6kg of force to lock-up the wheel.

    Therefore, a rim brake caliper only has 0 to 105kg of range to apply force, while the disc brake has 0 to 528kg of range. This extra range is modulation.

    It can be argued whether or not extant disc and rim calipers have equivalent fine control within those ranges, but the physics says that the disc has better modulation. Obviously both systems can stop the wheel, and the argument for discs has never been (or should never have been) about superior force, but about finer application of that force.

  • Jay

    Old school and traditionalist. I’ve never seen any riders complaining about shifting speed and reliability, or the bike is not compliant enough with 19mm tyres over the cobbles. Why change them?

  • Norfolk_n_Chance

    Oh thank god, another chipper agreeing with me!