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Old 09-25-08, 09:05 PM   #1
PaginaVilot
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Can't setup rear V-Brakes..

I got new cable housing today as my previous setup was all mismatched colors.

When the rear brake is engaged everything is fine, but when I let go, the part of the cable on the top tube (where there is no housing) looks very slack. If I were to slightly touch it with my leg, it becomes very slack and sort of just hangs there. If I engage the rear brake, it tightens up again.

There's also a really annoying clinging noise everytime I go over a bump from the cable hitting the frame.


I've tried all kinds of adjustments and can't get it right. Do I need a new brake cable?
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Old 09-25-08, 09:25 PM   #2
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Try taking some wax-based lube and spraying it down inside the housing. Also, check to make sure your housing is properly fitted inside the brake lever. It should go some ways inside the lever and stay there when the lever is pulled and released. Check down at the brake for the same thing.
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Old 09-26-08, 01:22 AM   #3
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I'd tighten the cable.
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Old 09-26-08, 11:17 AM   #4
Joshua A.C. New
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Once or twice, I've shot teflon lube down a cable housing, but most of the time, this means a cable's broken somewhere. $3 will set you up.
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Old 09-27-08, 05:16 AM   #5
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Quote:
Originally Posted by PaginaVilot View Post
I got new cable housing today as my previous setup was all mismatched colors.

When the rear brake is engaged everything is fine, but when I let go, the part of the cable on the top tube (where there is no housing) looks very slack. If I were to slightly touch it with my leg, it becomes very slack and sort of just hangs there. If I engage the rear brake, it tightens up again.

There's also a really annoying clinging noise everytime I go over a bump from the cable hitting the frame.


I've tried all kinds of adjustments and can't get it right. Do I need a new brake cable?
By your description, it appears the brake lever is pulling the cable sufficiently (which they usually do) but when the brake lever/cable is released, the brake arms are not pulling the cable back.

A cable not pulling back can be due to three problems. 1) Cable fiction 2) brake arm spring back tension too weak, or 3) combination of 1) and 2).

If you are getting slack at the top bar then the potential cable binding is futher aft. It could be at your cable stop on the top bar or at/in/around the brake noodle.
Disconnect the noodle from the brake arm and pull the cable back and forth through the noodle and note the drag effort.

While disconnected, note how "springy" your brake arms are. The spring back tension of the brake arms have to compete with cable friction in order to release the brakes. If you have weak spring back tension and higher than normal cable drag ... your brakes will probably work when applying the brakes but have troubles releasing the brake.
Some brake arm mounts have three spring tension holes that the spring is inserted into. If the assembly is in the milder spring tension hole and you have cable friction, the brakes may not release.

So you need either less cable friction or more brake arm spring back tension or both.
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Old 09-27-08, 05:30 AM   #6
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sounds like you have a snag on the brake outer casing.
look in the ends of the housing. check to see if its got a clear hole.
sometimes I work a dart into the cable end to make sure its ok

also if you have a suspension bike they sometimes have bad cable routing.
check that the housings are long enough to not get strained on suspension compression
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