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Dia Compe 872 Canti Brakes(5 posts)

Dia Compe 872 Canti BrakesCT1 Guy
Dec 26, 2002 12:13 PM
Just picked up an old set of 872 Cantis on close-out - bagged up with no instructions. Have built onto bike, but find that all springs are wound in same direction, so LH brake is 'unwinding' when tensioned. Makes spring tension extremely uneven and make's centering difficult as I have to use a pivoting hanger. Have I been given a mis-matched set or are they all like this. Would seem to be eminently more sensible to have opposite brakes springs wound in each direction?
flip the spring on one brake? (nm)Kerry
Dec 26, 2002 6:25 PM
re: Dia Compe 872 Canti Brakespa rider
Dec 27, 2002 10:25 AM
Hey CT1. Does the brake have a 10mm nut when sliding to brake boss. I never had this model, but the old 86-# model (I can't remember the model number last digit) . I nevered noticed any spring preferance in direction. You do know how to tighten the tension easily?

I'm not arguing, but found the cantalever brakes were easy principle to adjusting tension, until they got packed with mud. Left side rubs you tighten it or loosen the right side. I know after 1995 they started putting nuts to help you tighten the spring tension.

Did you look into using a v-brake setup? I'm looking at building a cross bike next winter and found they do have a cable routing device that can be use on cross bikes to allow V brakes be installed. It looks like a "Roll a jamma" that we use on mtb rear derailer.

I always hated those cable hangers. Good luck. I have a bunch of old springs in my tool box from those days. I don't throw out old parts, because you may one day need it to fix a kid's bike.

re: Dia Compe 872 Canti BrakesCT1 Guy
Dec 27, 2002 10:53 AM
Thanks for your answers guys.

Flipping the spring isn't the answer - the problem is that the springs are both wound the same way, so they both exert pressure from left to right, when I want one to go from right to left.

Vee's aren't an option as it's a cross set-up on an old MTB frame - I've just taken the Vees off. I've set-up Vee's with pulleys before and there's virtually no modulation- something I would like.

Fortunately, I've got them to work, but the mechanic in me doesn't like the set-up and I want to improve it.
re: Dia Compe 872 Canti Brakestjl
Dec 27, 2002 10:29 PM
Remember that centerpull cantilever brakes' leverage can be adjusted by changing the height of the straddle cable. Higher leverage makes it easier to brake, but requires more lever travel and is less tolerant of untrue wheels (too much leverage means that you'll bottom the lever out before you get maximum braking). Lowering the straddle increases the leverage, while raising the straddle decreases the leverage.

Nashbar has Shimano Alivio centerpull cantilever brakes for sale for something like $8 each.