Compass Centerpull Brakes for Bolt-On Mounting

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We now offer Compass centerpull brakes with a backing plate for bolt-on mounting, in limited quantities. Many customers have asked for this: Wouldn’t it be nice to get the superlight weight and superior performance of these brakes on an existing bike?

A backing plate connects the pivots with the fork crown, which makes it possible to bolt these brakes onto any bike with brake-mounting holes in the fork crown and in the rear seatstay bridge. You’d get much better performance than most other long-reach brakes, which often suffer from excessive flex and offer only poor braking performance.

For us, the problem was cost: A backing plate requires a new forging die, which is very expensive. We would have to sell hundreds of bolt-on brakes to amortize this cost. We could CNC-machine the plate, but then it would have to be much larger to offer the same strength, negating the light weight and elegance of the forged Compass brake arms. What to do?

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At this point, I was reminded of Preston Tucker, who introduced his revolutionary “Torpedo” in 1948 (above). Unable to get his new torque converter transmission ready in time for the car’s launch, Tucker’s engineers realized that transmissions from old Cords could be used in the new Tucker. So Tucker’s team scoured scrapyards to recover these transmissions, which were rebuilt with strengthened parts and installed in the first Tuckers.

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I realized that the backing plates we needed also were lying around in parts boxes and junk bins: They had come off old Mafac Raids when builders used those brakes with brazed-on pivots. In fact, I had a set myself, left over from building my René Herse way back before Compass brakes were available. The backing plates don’t wear out – any play in the bushings comes from wear of the aluminum arms, not the steel pivots – so the old Mafac backing plates remain as good as new. We found a number of these, and had them refurbished and polished by our friends at Norther Cycles in Portland.

Now we are offering the Compass centerpull brakes with backing plates. The brakes are sold individually, with all the hardware needed for bolt-on mounting. If your frame has recessed brake holes, you can either use the supplied bolt and nut, or you can modify the bolts and use recessed nuts.

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Of course, the backing plates add some weight and flex, so they’re not the ultimate solution. If you are thinking about repainting your frame anyhow, just have a framebuilder add the braze-ons and use our standard centerpulls. That is what Steve Frey did on his “hot-rodded” Trek (above), which we featured in the Winter 2016 Bicycle Quarterly. Or add braze-ons to the fork (as well as rack-mounting eyelets) and use a bolt-on brake on the rear, where you don’t need that much braking power.

Quantities of the bolt-on centerpulls are limited by our supply of backing plates. And if you have a spare set of Mafac Raid backing plates (distance between pivots: 75 mm), or a spare set of bolts and hardware for bolting the backing plates onto the frame/fork (all models), please get in touch. Like Preston Tucker, we are paying good money for what otherwise would be useless parts.

Click here for more information about Compass centerpull brakes.

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 high-performance components for real-world riders.
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18 Responses to Compass Centerpull Brakes for Bolt-On Mounting

  1. How much additional weight does the backing plate add to the brake assembly? My guess is the weight is insignificant.

    • The backing plates actually are quite a bit heavier than the arms, because they take significant loads. So the weight of the brake increases significantly… but when you look at the weight of bike and rider combined, it’s not significant. The specs on the Compass web site include the weights.

  2. Gugie says:

    I have backing plates-email sent!

  3. Frank says:

    An illustration of at least two things: the advantages of having standards and how there are entrepreneurial opportunities in sustainability.

  4. Vincent Russell says:

    This is great news. It’s a nice touch that you took the time to polish the backing plate.

    I saw somewhere that you also might be having some bosses made for titanium frames – or at least there was some hint of it. Is that the case? If so, when do you think that they might be available? I know that you can’t say exactly, but even an order of magnitude – 2 months, 6 months, one year – would be helpful to those of us who are having frames made and would like to use you brakes.

    Thanks Jan. Keep up the great work.

  5. Steve Frey says:

    What a crazy, but totally awesome idea! As you know I love finding ways of bringing old bike stuff back to life and keeping it out of landfills.

    I have a couple sets of old RAID backing plates I’ll be sending to you as soon as I can dig them out of the spare parts box.

  6. Bob says:

    The catalog listing includes a link to rack-mounting bolts. Does that mean the bolt-on model will support the CP-1? With a reasonably loaded handlebar bag? Thanks.

  7. Garth says:

    My initial thought was why you’d have new ones made when there are so many (still?) out there. Then I realized I was thinking about the Weinman/DiaCompe plates and wondered if those are interchangeable? Maybe not as pretty…

  8. Frank says:

    I am much impressed at the thought of using pre-loved parts. Well done Compass. Bravo! Chapeau! Best, Frank

  9. anonymous says:

    Have you measured the reach?

  10. Bert says:

    This question is not directly related, if you excuse me. I have Raid brakes, but the mounting bolt is for vertically drilled seatstay bridge. Are the bolts you are selling also vintage, or are they newly manufactured? I would be interested to order those bolts together with other minor items from Compass, like the new decaleur. Many thanks.

    • The bolts are also old Mafacs, so we cannot sell them separately. (The cost of making a custom bolt is almost as high as that of a forging die, because the minimum quantities are very large.) However, any Mafac bolt will fit, and those for the more common models (especially the Racer) are plentiful.

  11. Thinking about re-purposing old parts… hove you thought about selling Compass chain guards? Like the ones in you CX bike, but made out of old, worn out Compass chainrings.

    • Neat idea to make cyclocross chainguards out of old chainrings. Fortunately or unfortunately, René Herse chainrings are made from super-hard 7075 aluminum and last too long for this to be practical – there simply aren’t many worn out ones yet, even six years after they’ve been introduced.

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