Introduction

This article is for:

  • everyday cycling (not racing, or down-hilling etc.)



 

WHAT YOU NEED TO KNOW

PRECONDITIONS: You have a safe place to investigate and test your brakes - what kind of problem is there? and are your brakes now working properly?

TIME: 30mins-1hr depending upon the problem.

DIFFICULTY: Mostly easy (to replace pads and align components), but overhauling 'stuck' mechanisms may be more difficult.


POSSIBLE ADJUSTMENTS


A. Brakes do not grip

B. Noisy brakes

C. Brakes stick / do not spring back

 



A. Brakes do not grip


sidepull brakes
On side-pull brakes, use the centering screw on the top of the brake.
cantilever brakes
On cantilever brakes, adjust the pads directly.

Brakes "do not work" in the sense of not gripping the rims for several possible reasons.


Problem Adjustment

worn brake pads

Fine adjustment: Tighten the grip of the brake arms, by unscrewing the cable adjusting screw (located either where the cable meets the brake arm, or where the cable meets the brake lever).

Large adjustment: Shorten the 'effective length' of the brake cable. With one hand, squeeze the brake arms together and against the rim. With the other hand, unscrew the anchor bolt, and pull the brake cable until it is tight, relax the cable a millimetre or two, and then tighten the anchor bolt. Then make fine adjustments with the cable adjuster.
A 'third-hand tool' holds the brake pads against the rim, so that you have 2 for playing with the cable and anchor bolt.

brake shoes not aligned

Directly adjust the brake shoe so that the pads follow with the arc of the rim. Check the pads are not rubbing against the tyre, and not crossing the edge of the rim.

quick release tab open (up) On side-pull brakes use the centering screw on the top of the brake. On cantilever brakes, adjust the pads directly.
wheel off-centre Check the wheel sits in the frame dropouts correctly. If the wheel is warped, straighten the wheel


B. Noisy brakes


 
brakes toed-in
Brakes are noisy if brake pads are not correctly "toed-in".


Noise Adjustment
squeak, squeal, screech

rim or pads oily or dirty– just give them a good clean!

brake pads not correctly “toed-in”

When you apply the brakes, the front of each pad should touch the rim fractionally before the rear of the pad - facing forward, the “toes” of each pad should be a millimeter or so nearer the rim than the rear of the pad (hence “toed-in”). The rotation of the wheel pulls the pads parallel and against the rim.

split rim
To avoid split rims, remove any grit from the brake pads.


Noise Adjustment

grit in the pad

Grit scores the rim, ultimately wearing the rim through (see picture). Best winkle out any grit or replace the pads before the noise gets expensive.

 


C. Brakes stick / do not spring back


Clean and lubricate dirty or rusty pivot: Brake arms rotate on a pivot. Over the years, this pivot may become so dirty and/or rusty that the brakes get ‘stuck’ in the 'on' position. Clean the pivot thoroughly (removing any rust with wire wool), and relubricate it.


 
remove cantilever brake arm
On cantilever brakes, undo the pivot bolt and remove the brake arm.

  • Cantilever brake

    Pivot on a boss attached to the frame. To access the boss, disengage the straddling cable, undo the pivot bolt, and remove the brake arm. Then pull off the arm and clean, de-rust and grease the boss.

clean and grease brake boss
On side-pull and center-pull brakes, clean and grease brake boss.

  • Side-pull and Center-pull

    Side-pull brakes have one or two pivot bolts at the base of the brake arms. To access these bolts, loosen the locknut (on the rear of the brake arm), and then unscrew the pivot bolt on the front.

    To adjust the pivot bolt, screw it in completely, and then undo it slightly, before tightening the locknut. (Securing the locknut slightly tightens the whole mechanism.).

 

Results


responsive image

Brakes feel responsive




Bike Fixer

photo of mc

Bike Fixer is a co-op of bikers and web designers.
"mc" grew up car-free in the countryside, and had to ride a bike from an early age - absolute magic! In later life, he survived London traffic and l'Etape du Tour.


Sources

The books below are tremendously helpful, but there is a lot of material to get through.


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