Brake pads are an integral part of stopping. They rub against the wheel rim, causing friction that slows down the wheel. This process, together with the heat generated, wears the pad’s surface and, eventually, the rim surface. If the pads are worn beyond the wear line or the grooves are no longer visible then it’s a good time to learn how to change brake pads and replace them as worn pads will not only compromise the braking power but may also wear the rim much quicker.
The three main rim brake pad systems
- No stud/ road- The pad is attached to the caliper arm using a bolt. There might be a small washer but the angle adjustment is limited. These types of pads are used on road calliper brake systems.
- Threaded stud- The pad is attached to the brake caliper arm using two sets of shaped washers, a load bearing washer and a nut. They allow a perfect position and angle alignment of the pad. They are used on V-brake and modern cantilever systems.
- Smooth stud- Type of pads found on old cantilever brakes. It has a threadless post that is clamped by the caliper’s mechanism that also allows the pad to be adjusted in different angles.
A word about washers
Whatever pads are being fitted, there will be a nut or bolt holding the brake pad in position. Underneath this will be a washer. This stops the spinning nut from catching the spacer underneath it and provides a bigger surface to help bear the load of the tightened nut. The load bearing washer has a different surface on each side.
In some applications, the direction of a washer can be the difference between a component failing or not, but with any brake pads the direction doesn’t matter. If you want to fit the washer as recommended by washer manufacturers, then the rough side goes on first to dig into the spacer below and the shiny side is uppermost to help the rotating nut spin freely.
How to change brake pads– pad attachment
The pads come as one piece or a cartridge system.
One piece– The rubber braking surface and the metal stud are moulded together. They are cheaper to make but require more adjustment during installation.
Cartridge system- The rubber breaking surface slides into the metal body. The shoes can be swapped quickly and without losing adjustment. Great for when the pads are being worn frequently or when changing the riding conditions. The pads are generally cheaper than buying one piece and, of course, use less global resources.
How to change brake pads– tools required
- 4 or 5mm allen key or 10mm spanner to remove the nut or bolt.
- 2 crosshead screwdriver or 1.5-2.5mm allen key to remove the retention screw.
- Long nose pliers to remove the retention clip and help to push out the cartridge.
How to change brake pads– preparation.
Before you start, check that your wheel sits in properly and that the rim doesn’t have any major buckles.
Check if the new pads are directional. Some pads have either an arrow, a letter (L or R) or both written on the top of the pad. Fitting pads in the recommended direction will maximise water and dirt clearance.
How to change brake pads– Road pads
- Make sure that the barrel adjuster is screwed all the way in.
- Undo the quick release lever near the pad.
- Squeeze the appropriate brake lever, unscrew and remove the nut or bolt on the pad.
- Now remove the pad
- Put a small amount of grease on the thread of the new pad.
- If the pad comes with a concave washer, place the dipped side over the bulge on the pad.
- With the correct orientation, place the new pad between the rim and brake arm.
- Fit the bolt and load bearing washer and hand tighten.
- Road pads also come with guidance fins below the breaking surface. They help to guide the wheel into position when refitting.
- Now, with one hand squeeze the appropriate brake lever just tightly enough to be able to move the pad around. With the other hand position the pad so that it sits squarely on the rim with about half a millimetre of rim showing at the top. Too high, and it may rub on the tyre causing premature wear. Too low, and not all of the pad will touch the braking surface, wearing unevenly and causing the brake to catch on the underside of the rim.
- Squeeze the brake so that the pad can’t move.
- Using an allen key start turning the bolt until it resists.
- Now still holding the brake lever, put the allen key in an upright position.
- Put your index finger against the bottom of the pad at the front and use your thumb to turn the allen key. Do this in small increments repeating the process until you can’t tighten it any more.
- Now release the brake lever, grasp the pad with one hand and do a final tighten.
- Close the quick release mechanism.
How to change brake pads– Threaded stud pads
- Make sure that the barrel adjuster is screwed all the way in.
- Release the brake calipers.
- Unscrew and remove the old pad.
- Take the new pad. There is a nut and next to it is a load bearing washer. Then there is a concave washer, 2 identical convex washers and finally another concave washer. The 2 concave washers vary in depth.
- Check the washers on the brake pad that is still on the bike. On your new pad, fit the concave washer that matches the one on the existing pad. Put the flat side on first so that the dip is uppermost. Now fit one of the convex washers so that the dome fits inside the dip.
- Put a small amount of grease onto the thread.
- Make sure that the rest of the washers and the nut are in easy reach.
- Fit the new pad with the correct orientation, push both brake arms against the rim and hold in position with one hand just tightly enough so that you can still adjust the pad.
- With your free hand, position the pad so that it sits squarely on the rim with about half a millimetre of rim showing at the top. Too high, and it may rub on the tyre causing premature wear. Too low, and not all of the pad will touch the braking surface, wearing unevenly and causing the brake to catch the underside of the rim. The dipped and domed washers will settle into place, allowing the pad to push evenly on the rim.
- While still pushing the brake against the rim, look at the brake arm. The aim is to have it as vertical as possible. The position can sometimes be improved by swapping the concave washers.
- When you are happy with the position of the pad and washers, fit the convex washer, flat side first, then the concave washer so that the dip goes against the dome, then the load bearing washer and finally the nut.
- Using an allen key start turning the bolt until it resists.
- Now, still holding the brake arm, put the allen key in an upright position.
- Put your index finger against the bottom of the pad at the front and use your thumb to turn the allen key. Do this in small increments repeating the process until you can’t tighten it any more.
- Now release the brake arm, grasp the pad with one hand and do a final tighten.
- Repeat the process on the other side.
- Now refit the brake noodle.
How to change brake pads– Cartridge brake pads.
- Remove the wheel. This will give you better access to the pads.
- Using a screwdriver or allen key remove the retention screw or clip.
- Now slide the brake shoe out. If it’s hard, use the pliers to help push it out.
- Fit the new brake shoe with the correct orientation. There is a groove at the back of the pad. This is where the retention screw or clip sits in.
- Refit the retention screw or the clip.
- Repeat the process on the other pad.
- Put the wheel back on.
- Close the quick release mechanism on the caliper.
Your brake pads are one of the most essential parts on your bike. They determine just how effective your braking system will work, especially in wet and slippery conditions.
Overtime, bicycle brake pads will become worn out making them less effective. As they become less responsive, your chances of accident or damage to your bicycle increases.