Maintaining your brakes
- By London Cycling Campaign on at 07:12pm 18 Sep 2011
- Posted in: Advice, Bike maintenance
- Tagged with: e, 4
Most brakes systems involve you squeezing a lever on the handlebar so a cable or hydraulically operated caliper squeezes the wheel rim or a hub-mounted disc or the hub itself.
Your brakes must be able to stop your bike effectively, without you having to squeeze the lever tightly against the handlebar.
Cantilever, V brakes and side-pull brakes work by squeezing pads against the rim, and are the most common type.
It's worth learning to maintain these yourself to save money and avoid the inconvenience of taking your bike to a shop.
Adjusting your brakes
If your brakes are not strong enough, you can add power to them by making small adjustments with the adjusting screw or barrel adjuster, which will either be where the cable comes out of your brake lever or at a cable-stop.
On side-pull brakes it may be where the cable meets the brakes.
You will need to loosen the locking nut on the inside of the adjuster, and then you'll find that screwing the adjuster out takes up slack in the cable. This should make the brake more responsive by effectively shortening the cable.
Once you are satisfied with your adjustments make sure you re-tighten the locking nut.
To make larger adjustments, you can tighten the cable manually: loosen the cable clamp bolt enough to allow the cable to be pulled through with pliers (or fingers).
Then pull the cable through a small amount, tighten the bolt, test the brakes and if satisfied fully tighten the bolt.
Replacing brake blocks
If your brake pads have worn down then you will need to adjust or replace them.
NEVER let your brake pads wear down so that the metal scrapes the rims or you'll damage expensive rims.
If replacing the brake pads, pay attention to how they fit and the order of any spacers or washers for fitting the new set.
Whether you are adjusting or changing your brake pads you need to make sure they are aligned correctly, so that when in use they are fully touching the rim and do not touch the tyre.
Place them so that they are no more than 3mm from the rim when not being applied. If they rub in places you may need the wheel trued.
If your brakes squeal, 'toe in' the brake blocks - the front of the block should hit the rim fractionally before the back, or replace worn blocks.
Replacing brake cables
Over time cables will stretch and need replacing. If your cables are damaged, frayed or sticking you should replace them.
You can remove the cable by undoing the cable bolt (see ‘adjusting brakes’), cutting off the cable cap end and sliding the cable through the casing and out of the levers.
Pay attention to how the cable is threaded and fits through the lever for when you put in the new cable; there should be slots in the lever to allow the cable to fit in and out easily. This is a good time to lubricate the cable casing with some light oil.
Fit the new cable from the lever, back through the outer and down to the brake. There are two types of cable end: pear shaped for drop handlebars and barrel shaped for flat handlebars.
Make sure you tighten the cable clamp fully once you have set up the correct tension (see 'adjusting brakes’). If your brake levers have a slot for easy cable installation, make sure the corresponding slot in the adjusting nut is positioned so that the cable won't come out by accident.