ALL ABOUT BRAKES!
There are three major types of bicycle brakes: rim, coaster and disc.
Coaster brakes use a mechanism inside the rear hub to stop the wheel from turning and require you to push backwards on the pedals to stop.Coaster brakes should be taken to a shop for repair or adjustment.
Rim brakes apply force to the wheel rims to stop them from turning and are available in a variety of types including cantilever, linear pull ("VEE") and sidepull (Caliper).
Disc brakes apple force to metal discs, called rotors, attached to the wheels to stop. Like rim brakes, disc brakes are activated by hand levers. Take disc or coaster brakes to your mechanic unless you are confident you can correctly adjust them.
ADJUSTING BRAKE PADS
Squeeze the brakes with medium force until the pads contact the rim. Loosen the nut that holds the pads in the brakes. Align the pads firmly against the rim and tighten the nuts.
If your Bike has disc brakes, take it to a local bike shop for service and advice. Rim brakes all work in much the same way. There are different kinds including cantilever brakes, linear pull brakes and caliper brakes.
This simple job is often not only the solution to squealing, rumbling or vibrating noises, but may also solve inadequate braking performance and prevent serious mishaps. As the brake pad wears, its position relative to the rim changes. You should regularly check the position of the brake pads as they contact the rim, and readjust them if they don't align. It is also preferable if the front end of the brake pad is about 1/16 inch (1mm) closer to the rim than the rear. This is to compensate for the bending of the brake arm as you squeeze the brake. Only when you adjust them this way, referred to as toe-in, will the brake work properly.
Tools and equipment needed
5 mm Allen wrench
9 or 10 mm wrench
Rim Brake Inspection:
Check to make sure the wheel rim and brake pads are clean. If not, use Simple Green and a green scrubby pad and clean the side of the rim until all of the built up black rubber is gone.
Remove the brake pads and lightly sand the pads with 100 grit sandpaper until the pad is roughened up.
Squeeze the brake and let go quickly to ensure the cables aren't sticking within the housing. Enlist the assistance of a bicycle mechanic if you find difficulties with the cables or housings.
Inspect the levers - they must be firmly installed and there must be at least 2 cm (3/4 inch) clearance between the lever and handlebars when the brake is fully applied. If necessary, tighten, lubricate, and adjust.
Make sure the brake arms move freely when the lever is squeezed and return quickly with the lever is released. The brake pads or arms should not rub the rim or tire when the lever is released.
Brake Movement Adjustment
The most common type of brake adjustment involves compensating for brake pad wear by tightening the cables. First, make brake pad adjustments. If the brake still does not grip well or the lever travels too far, a cable that is slightly too long is the most likely cause. Adjust initially by loosening the barrel adjuster counter-clockwise on your brake lever or brake until the brake engages when 3/4" clearance remains between lever and handlebars. A barrel adjuster at either end of the housing may be turned counter-clockwise to "lengthen" the cable housing, moving the pads slightly closer to the rim. Or, the barrel adjuster may turned clockwise to "shorten" the cable housing, moving the pads slightly away from the rim.
If the brakes have no fine adjustment feature, the following steps must be taken for all adjustments:
1. Loosen the anchor bolt
2. Pull a little of the cable through the anchor bolt,
3. Re-tighten the anchor bolt
Ideally, brakes should not get so far out of adjustment that this step becomes necessary.
for a Road Bike Brake Adjustment Procedures
for Park Tool's instructions on Side Pull Brakes
for a Hybrid/Mountain Bike/Coaster Brake Adjustment Procedures
for Park Tool 's instructions on Cantilever Brakes
for Park Tool's instructions on linear Pull ("VEE") Brakes
for Park Tool's instructions on Coaster Brakes