Centerpull Brake Parts and Tools

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For our Compass centerpull brakes, we started with a design that had proven itself in decades of hard use: the Mafac Raid brakes. In fact, we had logged tens of thousands of miles on our own bikes with these brakes. We thought hard about how to improve them, but apart from a few minor tweaks, the Mafacs appear unimprovable. The one thing we could improve is the quality. The original Raids were budget parts – well-designed, but the finish and tolerances often were mediocre.

That means that the Compass brakes use old-style canti brake shoes, which have a few significant advantages.

  • The brake arm isn’t twisted to accommodate the bolt-on brake shoes. This makes it stiffer and lighter.
  • You can slide the brake shoe inward as the pads wear, so there is no need for barrel adjusters or other mechanisms to take up pad wear. Since you’ll reset the pad angle, there is less risk of the pad starting to cut into your tire as it wears and hits the rim higher up.
  • Adjusting the pad angle is easier, because you can grip the pad holder as you tighten the bolt.

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Mafac used to make a nifty tool to hold the pad holder in place as you tighten the nut. Grand Bois has re-introduced this tool, and we have it in stock. It’s beautifully finished, but most of all, it makes working on centerpull brakes (whether Compass or Mafac) so much easier.

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We made sure our hardware is interchangeable with the classic Mafac brakes, since we could not improve upon their design.

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So if you have a brakeset with sloppy bushings or rusty bolts, you can rejuventate them with our Replacement Hardware Kit. The arms themselves never wear out. Polish them up, and install the new hardware, and your brakes look and perform better than new.

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To remove and install the bushings in the brake arms, Compass offers a simple tool. Use a hammer and gently tap the old bushings out of the brake arms. Then use the same tool to tap in the new bushings.

The holes for the Mafac pivot bushings have somewhat loose tolerances, so we recommend reaming the holes in the brake arms to make sure that our bushings fit. You need a 10 H7 reamer (10 means 10 mm, H7 is the tolerance of the fit), which is available in good hardware stores.

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Kool-Stop offers replacement brakes pads for Mafac brakes. They come in the normal length (4-dot) or extra-long for tandems (5-dot). Kool-Stop offers them both in their excellent salmon-colored compound for superior wet-weather brakes, and in black for restorations. We use them on the Compass brakes, and also sell them separately.

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For the straddle cable hanger, we could not resist using the lovely René Herse rollers. Apart from the domed nut that is a slightly taller shape (so it will not bottom out, unlike the originals), the René Herse straddle cable hanger is an exact replica of the original, which is great for restorations of classic René Herse bikes. Of course, they also work great on other bikes. You have the option of letting the roller turn, which automatically centers the brake every time you apply it. If your brake springs have uneven tension, you can reverse the screw that holds the roller so that it does not turn. Then you can set the straddle cable position where you want it, and it won’t change. It’s a smart design – once again, we could not improve upon it.

BrakCmRhStraddle

We also offer replacement straddle cables for some Mafac 2000 brakes. They also fit some “Competition” models, but the straddle cable hanger may be higher than before. Fortunately, with centerpull brakes, the mechanical advantage does not change significantly with straddle cable height. (These straddle cables do not work for brakes that require the ball-end straddle cables.)

The Compass brakes use a standard shifter cable as the straddle cable, so you won’t need to worry about spare parts availability.

Click here for information about these and other Compass brake parts.

About Jan Heine, Editor, Bicycle Quarterly

I love cycling and bicycles, especially those that take us off the beaten path. I edit Bicycle Quarterly magazine, and occasionally write for other publications. Bicycle Quarterly's sister company, Compass Bicycles Ltd., turns the results of our research into high-quality bicycle components for real-world riders.
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25 Responses to Centerpull Brake Parts and Tools

  1. Brian Campbell says:

    I used the Compass kit to re-build set a of MAFAC Racers. It was easy and the brakes work great. No squealing and fantastic stopping power. I did have to ream out the Compass brass bushings to fit on the MAFAC mounts.

  2. Jon H says:

    Hi, curious about the GB brake shoe adjusting tool – if I could ask, do you have an ‘in action’ photo of how this works? Thanks!

  3. Frank says:

    Hi Jan.

    Any chance that you could make your excellent brake available as a ‘single’ and not only as a ‘pair’? I only need a front brake for a fork I’m hoping to get built … and will leave the less important rear brake ‘as is’.

    Thanks. Frank

    • I am surprised that there is demand, but it should be easy. We’ll look into it.

      • Frank says:

        Thanks Jan. I’m replacing a carbon fork … and figure I may as well ask the frame maker to go with a centrepull brake even though it won’t match the rear. The majority of my riding is up the mountain at my backdoor … and I spend a lot of time contemplating brakes on the way back down.

      • I think it will start making sense for brake manufacturers to start selling single rear calipers. I can see more riders retrofitting front disc forks and disc brakes, but leaving the rear caliper in order to save weight (and because you only need the extra power and modulation of the disc in the front anyway, at least on paved roads).

  4. thebvo says:

    I think you mentioned in an earlier post about a rinko ready hanger cable with a QR on both ends. Is that still in the works? Also, is there a reason why you wouldn’t want both sides to be easily opened?

  5. Rick Harker says:

    I couldn’t see any adjustment for toe in/out. is this possible with this brake?

  6. dylan varekamp says:

    man, i never thought i would see stiffer/lighter as an excuse for extremely poor adjustability on the compass blog. the mafac design is a real bear to set up properly when compared to the paul version or even a decent quality dual pivot brake. not to say that you can not set them up to perform beautifully, but setting them up is so much more difficult than it needs to be, and all you get in exchange for the added difficulty is a marginal improvement in brake feel. if you get a good quality dual pivots or even the paul center pulls, you will have toe in, adjustments are quick and easy and need no special tools. and roller hangers! they put the whole load of your braking on a single small point instead of spreading it over the arc of one of the stamped and folded straddle hangers. i love y’alls tires and frame building gear, but these brakes cost a lot of money for what they are.

    • I am sorry you seem to have had trouble with Mafac setup. We decided not to offer toe-in adjustment, because we find it very difficult with most modern brakes. It seems the pads always move as you tighten the bolts… Brake stiffness actually is very important for brake power and modulation, and we haven’t yet found a dual-pivot brake that fits 42 mm tires and offers adequate performance.

      I’ve set up Mafacs on dozens of bikes. You bolt them on, set the pad height and angle, and go ride. They may squeal for the first ride or two, and then they are quiet until it’s time to replace the pads many thousands of miles later.

      • Jon says:

        IMO, the rollers seem a better solution than the stamped and folded hanger because they self-center. It seems to me that the brake cable that is pinched by the top hanger bolt would fail or slip long before the roller axle would fail. Since stamped and folded hangers also install by pinching the brake cable, I do not see them as better even if they spread the load out at the bottom because the pinched cable is still the weakest link.

      • The Herse roller doesn’t pinch the cable, but draws it outward with an eyebolt. There is no risk of the cable breaking.

    • Wesley Gadd says:

      I’ve always found MAFAC brakes exceedingly simple to set up. As regards toe in, some may find it unacceptably crude, but the traditional way of doing it was with an adjustable wrench on the brake arm-a slight twist. I don’t do this in situ on brazed on pivots, rather I adjust each arm carefully in a vice before assembly. Again, some might not approve, but I’ve been doing this with MAFAC and Weinmann centerpulls for decades. Universals not so much-they had a reputation for snapping. I became enamoured of the adjustability of Shimano Deore and early 80’s Dia Compe cantis until actually trying to get the pads to hold adjustment as you tighten them. I’m back to MAFACs.

  7. Gabe says:

    Will the retrofit bushings work on Mafac Canti pivots, or are the canti pivots a different dimension?

  8. James says:

    Are those Hinoki shavings in the bag?

  9. Steve Green says:

    Two comments:-

    Selling front brakes singly makes sense; as the front brake does most of the work, it needs to be more effective than the rear. Campagnolo used to sell sets of a dual-pivot front brake with a single pivot rear.

    Toe-in (I assume to reduce/eliminate squeal). As squeal is caused by the beake mechanism flexing in use, trying to adjust the brake to stop it happening is merely compensating for poor design.

    • Garth says:

      Toe-in is to compensate both the flexion of material parts as well as the slop in pivots. Otherwise you’ll have the rear edges of the shoes digging into the rim, with very little contact area and a lot of shuddering/squeeling.

      Toe-in seems to something I’ve only set initially. Once new pads wear in they don’t require ongoing toe-in unless the brakes are of poor design.

      One example, IMO, of poor design are Tektri Oryxes that use the long, thin and thus flexible “v-brake” shoes. I found that if I didn’t continue to adjust them for toe-in, the backs of the shoes would flex inward, causing extremely poor modulation to the effect it was extremely easy to lock up the wheels, including the front.

      When I recently bought my daughter a bicycle with v-brakes and the dreaded pads, I went through great lengths to swap them for safer cantilever brakes.

  10. Jon Gehman says:

    Thanks for making the straddle cables available for Mafac Compititions! I really like those brakes and have them on 2 bikes, one vintage and one “modern”. After going to the trouble of polishing them and brazing up mounts I had to make my own cables from aircraft control cable and swaged ferrules, they work fine and are more than strong enough(I broke the cable on the ones I tested without the ferules ever failing) but their toolroom vibe looks out of place with the classic French aesthetic. The price is nice too. Well done.

  11. David Feldman says:

    Another toe-in comment. I’m a mechanic who started learning the trade in the “Mafac era.”
    If I could change anything on this brake, it would be to adapt the eyebolt hardware (wedge shaped washer with a tab for gripping, domed nut and washer behind the brake arm) of 1990’s Shimano cantilevers. This system made toe-in predictable and quick. It would be especially good to see this combined with a pad holder that fits modern road pad inserts–sure, the brake is a niche product but it might be nice if the most consumable part wasn’t. I have only set up one set so far and found the finish and mechanical quality of the main parts to be staggeringly good. I hope this is the beginning of revived centerpull brake appreciation and use!

    • We thought about the 1990s Shimano toe-in adjustment… but decided against it for a variety of reasons. I am glad you like the brakes! For the pads, they are easy to find, but in a pinch, any canti pad with smooth posts will fit. Every bike shop should have those, since they are still used on millions of mountain bikes from the 1980s and 1990s. So you’ll never be stranded!

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