Introducing René Herse Cantilever Brakes

The new René Herse cantilever brakes are here! Prototypes of these brakes were one of the secrets that made Peter Weigle’s bike at this year’s Concours de Machines so light. They weigh just 75 g per wheel including bolts, springs and pad holders (without pads).

How can the René Herse cantilever brakes be that light? After all, even carbon cantilevers like the TRP RevoX are 50% heavier at 113 g. The TRP shows what happens when you take a standard brake and try to make it lighter – there is only so much you can do.

The secret of our new cantilevers is simple: They are different in many ways from most current brakes. The credit goes to René Herse, who designed these brakes for the 1940s Concours de Machines technical trials, where his bikes were among the lightest ever made. And yet his brakes weren’t just for weight weenies – they even equipped his tandems. I’ve ridden Herse tandems in the mountains, and the stopping power of the brakes was definitely sufficient.

How do you make a superlight brake? You start with an absolutely minimalist arm. Ours is forged from aluminum for ultimate strength.

Just as important is the shape – we used Finite Element Analysis (FEA) to model the stress distribution in the arms (above). Blue and green means low stresses. As you can see, Herse’s original design showed no stress concentrations. (The small spot of red is caused by a lack of reference points near the edge, not because the arm is likely to break there.) The FEA model confirms the genius of the ‘magician of Levallois,’ who didn’t need computers to make parts that were light and strong.

The arms are so minimalist that there is nowhere to attach the springs. Drilling holes would weaken the arms, so the springs wrap around them instead. You’ll also notice that there are no screws to dial in the spring tension. They aren’t necessary, because our springs are carefully equalized. You only need to adjust the tension if one spring is stronger than the other – which unfortunately is the case on many cantilevers. Making springs to such close tolerances is more expensive, but it also makes setup easier.

René Herse used post-style pads. (In fact, he may have invented them – earlier cantilever brakes used the same pads as sidepulls, which attach directly with screws.) The advantages of post-style pads are many. First, it makes it easy to adjust for pad wear – you just slide the pads inward. This means that the brakes fit on bikes with a wide range of canti post spacing. The posts also allow adjusting for minor variations in canti post height (as you slide the pads inward, the arm rotates outward, which lowers the contact of the pad on the rim.)

Post-style pads make it possible to make the arms lighter, because they don’t need flat spots with slots where the pads attach. Herse used large eyebolts to attach the pads to the arms. This is one place where our new brakes are even lighter than the originals: Optional titanium eyebolts for the pad holders save weight without sacrificing strength – these bolts are large to fit over the pad holder posts, not because they have to withstand big stresses.

To adjust the toe-in of the brake pads, René Herse simply bent the arms. That worked for him, because his brakes were used only on custom bikes, which were set up in his shop by experienced mechanics. The advantage of this method is that you only bend the arms once, and the toe-in is set forever. Later, you can replace the brake pads without having to set the toe-in again.

For our new brakes, we offer the option of angled washers that let you set the toe-in (part 28/28T, shown above in blue). This is super-simple and permanent, too, so pad replacement is easy. Since the washers take up extra space, we replace the large aluminum nut on the eyebolt with a shorter steel one. The weight goes up a fraction (4 g), but it’s a great solution for customers who aren’t comfortable bending their brake arms, or for brakes that may be used on many different bikes. (Bending the arms too often can weaken them.)

Like our centerpull brakes, the new René Herse cantilevers use an extra-thin straddle cable. This is made possible with swiveling attachments to the arms, which eliminate stresses to the cable that occur with standard clamp bolts. The thinner straddle cable isn’t just lighter, it also bends more easily around the straddle cable holder. This eliminates the flex you get with thicker straddle cables, which have to straighten first when you apply the brakes, before they can transmit brake power. The thinner straddle cable makes the René Herse brakes more powerful, yet the minimal ‘lost motion’ allows you to set the pads with plenty of clearance to the rim – without the risk of bottoming out the levers. This also means that the René Herse cantilever brakes work equally well with modern ‘aero’ and with classic ‘non-aero’ brake levers.

We’ve tested the new René Herse cantilevers on a variety of bikes over hundreds of miles. They fit over 42 mm-wide tires with 62 mm-wide fenders, or 54 mm-wide tires without fenders. They are designed to work with cantilever posts that are spaced between 62 and 84 mm wide. To work with the ultralight design of these brakes, the height of your frame’s cantilever posts must be within standard tolerances. (Your current brake’s pads should be roughly in the middle of the slots.) If the pads of your current brakes are at the top or bottom of the slots, the René Herse brakes may not fit on your frame.

We are excited that we now can use these amazing brakes on many of our own bikes. For more information about the René Herse brakes or to order a set, click here. And if you’re curious about René Herse himself, we recommend our book on the ‘magician of Levallois.’

About Jan Heine, Editor, Bicycle Quarterly

Spirited rides that zig-zag across mountain ranges. Bicycle Quarterly magazine and its sister company, Compass Cycles, that turns our research into the high-performance components we need for our adventures.
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52 Responses to Introducing René Herse Cantilever Brakes

  1. 47hasbegun says:

    How well would these new brakes reduce the infamous cantilever squeal on a bike that has it bad?

    I have a Soma Double Cross that squeals so loudly that it echoes when braking hard. Toeing in only helps for a little while—much, much shorter than the life of the pads—and cleaning the rims every day is too time-consuming during the wet season. A Davidson I had built solves the issue by having the cable hanger at the fork crown, but the Double Cross doesn’t have the option due to the Nitto M-12SL taking up the hole.

    • Brake squeal can be hard to trace to a single factor. There are so many places where brakes can develop resonant frequencies. On all the test bikes, the new Compass René Herse cantis have been squeal-free from the onset. Is it because of the stiff arms and ultra-stiff pad mounting? Or because they are quality frames with canti posts that are very round and to the correct diameter? Or just pure luck? It’s hard to know. (I have ridden one classic Herse tandem where the brakes did squeal a little, but again, there were many factors involved.)

  2. Steve Palincsar says:

    Mafac used 5-dot pads on its tandem cantilever brakes. I presume this brake uses standard Mafac pads. If you were considering using the Herse cantilever on a tandem, would there be any advantage to switching to a 5-dot pad?

    • Larger pads don’t increase brake power. I think those Mafac 5-dot pads were mostly a placebo. René Herse didn’t use larger pads on his tandems, and we’ve ridden one of his machines with the same Kool-Stop pads that come with the new brake, with no problems braking or stopping even during mountain descents.

      • Steve Palincsar says:

        You quote the weight of the Herse brake without pads and compare with the TRP RevoX Carbon. TRP’s web site lists the weight of that brake as 118 grams “with hardware” but it’s unclear if they’re including pads as “hardware”. Assuming they are, how does the Herse brake compare to the RevoX Carbon when both are equipped with everything necessary for them to actually function as a brake?

      • Good questions! Of course, we compare like with like (both brakes without pads). The actual measured weight (with pads) for the TRP brakes is 128 g (from a review). The weight of the our Kool-Stop brake pads is 15 g. TRP’s pads are much thinner (and will wear faster), so they are a bit lighter. This means that the TRP brakes weigh a little more than 113 g without pads. The weight on the TRP web site (118 g) may indicate that they weighed them without pads, too.

  3. @d@v says:

    Hello Jan,
    A great product once again, but what about your previous comments about cantilever brakes ? You didn’t like them due to fork blades twisting when braking, thus offering inconsistent brake modulation.
    THank you for your answer.
    Sincerely.

    • The fork blade twist is inherent in the design. For a bike that is ridden in the mountains by a rider who likes to brake hard and deep into turns, I prefer the centerpulls. However, riding the Concours Weigle, I realize that many issues of cantilevers also are due to flex in the brake, and you have much less with these due to the stiff arms and super-stiff pad mounting. As to the fork blade twist, I’ve been thinking about using round fork blades that should twist less.

    • It’s ugly, but I’ve had really good luck using a horseshoe brake booster on my v-brakes. It firms up the braking quite significantly, I’m very happy with my brakes now. I think integrating that same function into a front rack would be a good solution to the aesthetic issue with the horseshoe.

  4. Phillip Cowan says:

    Looks like they are “Rinko Ready” also with slots on both arms. Awesome!

  5. Andrew Cohen says:

    Love the attention to detail on these! I have had bad luck with many sets of even high-end cantilevers (spongy lever feel, lack of power, poor match to cable pull of modern brifter levers, chatter), but I am hopeful that these might alleviate many of those issues.

    As a more specific question, can you comment on the comparison in braking power and reliability (chatter, etc.) between these and the Compass centerpull brakes?

    • The Compass centerpull brakes have a little more power and better modulation. That is inherent in the design – they attach to a stiffer part of the fork.

      The new cantilevers are even lighter, and they fit many existing frames, where the centerpulls require special braze-ons.

  6. Bill Lindsay says:

    This is really great. The product listing indicates that the price includes “a straddle hanger”, but there isn’t one pictured in the photos. Can we assume that it is a Rene Herse roller type straddle hanger?

    I was waiting to get cantilever posts installed by my local framebuilder for just this moment! Now I can execute.

  7. DaveS says:

    In the technical section on the order website for this brake, it states:
    Clearance for 54 mm tires without fenders, or 42 mm tires with 62 mm fenders

    If I have Rat Trap Pass tires with 62 mm fenders, will this brake fit?

    • That depends on the height of your fenders above the tires and on your canti post spacing. With wide spacing, the brakes open up more, and it may fit. In the future, we’ll probably offer an extra-long straddle cable that will help.

      • Jacob Musha says:

        Another vote for the extra-long straddle cable. I’d love to get these brakes on my bike(s) that have Rat Trap Pass tires and fenders.

  8. Chad K says:

    Are you going to sell a cable stop for the front brake like the one used on the Weigle? I am not aware of any currently available stops without adjusters.

  9. canamsteve says:

    Lovely! What is the minimum spacing for these cantis? I have a curly-stayed Hetchins and the front fork has a 55mm spacing between the canti mounts. That’s unusually narrow, but the frame and fork are matched and confirmed original,so there must have been a suitable canti brake available at the time it was built (1962). I have managed to cobble together a set of old Dia-Compes that work very well, but the clearance is *just* enough (27″ wheels)

    • 55 is very narrow! What happens with these brakes is that the arms drop down so much that the mechanical advantage decreases, and at some point, the pads no longer line up with the rim. After measuring many bikes, modern and classic, we designed the brakes for a pad spacing of 62-84 mm. This doesn’t mean that values outside this range won’t work, but we can’t guarantee it.

  10. John Schag says:

    I’m a newbie with bikes. I have a 1982 Fuji lugged steel bike with 27″ wheels. Two questions re: these brakes:
    1) How do I tell if they will fit?
    2) Why would I use them instead of the original brakes?

    • If your pads are in the middle of the slots (and not at the top or bottom), these brakes will fit. Why use them? Lighter, maybe a bit more powerful (depends on the brakes you have right now), more beautiful… Usually, new, high-quality pads improve the braking more than anything, so a set of Kool-Stop salmon pads are probably the biggest upgrade you can make. If your bike has post-style cantis, you can use Compass pad holders and the pads we sell, but Kool-Stops are available in almost every imaginable configuration, and most good bike shops sell them. (Beware of other orange pads that look similar, but don’t perform the same.)

  11. Alex says:

    Jan, could you let us know which parts from the Rene Herse cantilever brakes are interchangeable with those from the Compass centerpull brakes (ie. which parts are identical) – and by extension with MAFAC centerpull and/or cantilever brakes. It may be relevant to some customers who’ve bought such items, or who own MAFAC brakes (for ex. brass bushings, titanium/regular eyebolts, both types of brake pad holders – do both fit all four types of brakes?, angled brake washers, etc).

    It might also be a good idea to sell the (cantilever) brake mounting bolts as a separate item: I’ve been looking for canti brake bolts everywhere and can’t find a source. They don’t seem to have the same size heads as V-brake bolts, but perhaps are interchangeable with V-brake bolts.

  12. I understand that the length of the straddle cable can be crucial for the performance of both centerpull and cantilever brakes. Is there a way to build custom straddle cables for those brakes whose cables can’t be adjusted?

    • On wide-profile cantilevers like these, the straddle cable length does not matter. Past analyses looked at low-profile cantis, where a shorter straddle cable both increases the mechanical advantage and the effective arm length. With wide-profile cantis, lowering the straddle cable decreases the effective arm length, which counters the increased mechanical advantage to roughly cancel each other out. Effective arm length is the distance from the straddle cable to the brake pad at a right angle. If you are interested, the Bicycle Quarterly ‘Brake Special’ (BQ 26) a more detailed analysis. That prompted Bello Benhumeur’s even more detailed study, which used to be online.

  13. Marciero says:

    The thin cables and no-bolt attachments are a nice detail.

  14. Dr J says:

    Interesting that these are supposed to be superlight brakes but they come with hex head screws that require you to use wrenches heavier than a simple 5mm hex (Allen) key. Makes no sense.

    • The main reason to use hex head bolts is for the front (or rear) rack attachment. The René Herse rack mounting bolts feature a forward extension onto which a rack can be mounted more securely than if it is sandwiched on the same Allen bolt. With an Allen head, the hole needs to be where the forward extension goes.

      Also, your perception about the weights of the tools is incorrect. Allen wrenches are very heavy: A 5 mm Allen wrench weighs 17 g. A small Mafac 10 mm wrench weighs less than half that. Even the Rinko headset tool we sell (with 32, 10 and 8 mm sockets) weighs just 13 g. If you insist on carrying tools on the road, you can save significant weight with hex head bolts. That is the main reason we use them.

      But why carry tools for the brake bolts at all? They will never come loose if the bike is assembled correctly. During the Concours de Machines, I didn’t carry any tools beyond a spare tube, a patch kit and a single zip tie, because our parts don’t need maintenance on the road.

      • Dr J says:

        I get the part about rack. But regarding tools weight, the reason I like hex keys so much is that I can disassemble and adjust 90% of my bike with two hex keys (4 and 5mm) that weigh 22g total. Meanwhile, the small 10mm hex head wrench can be used only for these brakes because you can’t remove stem and fork with it. You need more tools for that.
        Sure, you don’t need tools on a neighborhood ride but on a week-long touring trip in more remote areas it’s good to have them.

      • In all my rides, only once did I a brake bolt come loose. That one was used to attach a rack as well as the canti brake, which made me appreciate the René Herse bolts that offer a separate extension. I then made my own bolts to the René Herse pattern, and never had problems again. We now offer these bolts with our brakes.

        I agree with you that it makes sense to standardize on a wrench type. The mix of sizes and types on modern bikes seems like such a lazy way to design bikes. Why does it take a 4 and a 5 mm to adjust the headset with most modern Aheadset-type stems? Since we use a hex head bolt on the front, we also use one on the rear…

        If you prefer Allen bolts, they are easy to find, and you can use them to attach Compass and René Herse brakes.

    • Matthew J says:

      A Park MT-1, tire levers and chain tool are all I’ve packed on multiple long distance tours and I’m anything but a weight weenie. Can’t imagine carrying separate Allen keys along with other tools you will need in any event could be any more light.

  15. Andy says:

    Nice design but very disappointing that they are made in Taiwan.

    • I share your concern, and initially, it may seem like a cost-savings measure to source parts from overseas. This isn’t the case.

      We would love to make our parts locally, but unfortunately, that isn’t an option. Nobody in North America has experience with forging lightweight bicycle components. Today, almost all forging for bike parts is done in Taiwan or China. Even TA’s and Campagnolo’s aluminum cranks are forged in Taiwan, because that is the place where the technique is available. If we wanted to fabricate our brakes in North America, we’d have to CNC-machine them, which would make them heavier, weaker and less elegant. It’s also more wasteful, with large amounts of aluminum converted to chips, which need to be recycled (i.e., melted down using a lot of energy). As to the bolts, cables and other small parts, I am sure that even those on ‘Made in the USA’ bike components are sourced all over the world.

      Legally, the René Herse brakes actually qualify as ‘Made in the USA,’ because they are assembled right here in Seattle. (For comparison, few parts of ‘American’ cars actually are made in the U.S., which is why so many assembly plants are located close to the Mexican border.) It’s just that we feel that our description should list the place where the individual parts are made, rather than trying to slap a ‘Made in USA’ label on them. The brake pads, by the way, are made locally, in Oregon.

      I wrote more about this topic a few years ago in this post.

    • I’ve seen this argument being used and then dropped in the musical instruments industry as well. As most consumers in the world, I don’t care where a product is made. Its quality and durability is what matters.

      Taiwan is hands down the center of bicycle technology of the world, and they can build exactly what they’re asked to. Wanna sell an entry-level product for a low price? They can do it. Want an exquisite piece of equipment for a very small market? They can do that as well. And since all major brands have their factories in Taiwan, the cost of manufacturing is much lower, even for a limited-sales item like Compass brakes.

      Of course there’s always some politics involved, and that’s why I stay clear of Chinese products. They might be good enough, but workers in the Popular Republic of China have no syndicates, no rights to ask for a better working enviroment or wages, and doing so is a sure reason for geting fired or incarcerated. None of that happens in Taiwan, so that’s another reason for doing business in the island.

  16. thebvo says:

    On my current cantis there is a hex on the front of the brake post which helps hold it in the correct possition while I tighten it on the back. This is super helpful because, as many of us know, tightening the bolt will twist the pad out of our desired alignment. Any tips to avoid the frustration during set-up?

  17. Are any parts interchangeable with the original Herse brakes please ?

    • The arms are the similar, but not the bushings, since the new brakes are made to make modern posts. The eyebolts and nuts will work on classic René Herse brakes, too. In the future, we will also reintroduce the classic René Herse brakes that work on Herse-style posts, and perhaps even the earliest models where the bolt formed the pivot.

  18. Toby says:

    Are the bushings on these brakes replaceable like on the centrepull brakes? I notice that the bushings on MAFAC cantilever brakes don’t seem like they are replaceable. Is this because they are unlikely to wear out compared to centrepulls?

    • The bushings on the new René Herse brakes are replaceable, and if a customer needs them, we’ll offer them separately. We offer the centerpull bushings mostly because they are useful for customers who are overhauling old Mafac brakes, not because anybody has had to replace the bushings on their Compass centerpulls yet.

      The Mafac canti bushings aren’t replaceable, because they hold the two plates together, so they are serrated and really mashed in there. They also don’t usually wear, unlike the plastic bushings often found on Mafac centerpulls.

  19. A Escolier says:

    Solution très élégante.

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