At this point in an upgrade, when you have the wheels, bottom bracket, crankset, pedals, handlebars and levers installed, you get to choose whether to install the brakes or derailleurs next. I’m going to cover the brakes first because there are fewer steps so it’s faster and ticks one more big thing off your build punchlist.
Note: for this series we’re assuming you are building a road bike with rim brakes, not disc brakes.
This Week’s Resource
The brakes discussed today are the standard sidepull brakes that come with upgrade component kits (also called “groups”). But, depending on your bicycle upgrade, you might be using a different rim brake type, such as older sidepulls and centerpulls or even cantilevers. To help, this feature story by Calvin Jones at Park Tool provides the steps for working on all types of rim brakes.
Brief Brakes Glossary
Sidepull brake: the generic name for the rim brakes on most road bikes
Caliper: the body of the brake
Brake arms: sidepull brakes are usually composed of left and right arms
Pivot(s): the brake post(s) that the arms pivot on when you brake
Adjustment barrel: a nice built-in feature on all quality brakes that lets you tighten/loosen your brake adjustment by hand
Centering screw: a small built-in adjuster used for small brake centering adjustments
Quick release: a little lever built into the brake caliper and inline with the brake cable that lets you open the brake for easier wheel removal/installation (because the tires are wider than the rims)
Cable anchor bolt: what you loosen and tighten during brake installation/adjustment to finish the adjustment
Brake shoes (also called pads): the parts of the brakes that rub on the rims to stop the bike
Double check the wheels first. In order to install the brakes correctly, the wheels need to be perfect. If not, fix them or have them fixed before proceeding. Check for these things:
1. The wheels must be true (straight) both side-to-side and up-and-down (no wobbles or hops).
2. Check that there are no dents or bulges in the rims (damaged rims may need replacing).
3. The braking surfaces on the rims should be sound (not worn badly), and clean of grit, grime and glazing or rubber deposits from the pads (clean with strong solvent or abrasive pad).
4. The wheels must be fully inserted in the fork and frame and tightened fully (check that the wheel quick releases are hard to open).
5. Push and pull sideways on the wheels to be sure there’s no significant play in the bearings. If there is, the bearings should be adjusted.
6. The wheels must also be centered in the fork (equidistant from the fork blades) and frame (equidistant from both the seatstays and chainstays).
This is a lot to check, but it’s worth it because it will ensure optimum braking performance for a long time. And just as important, it means you can take your wheels on and off and your brakes will keep working properly.
Mounting the Calipers
- There may be thread lock/adhesive already factory-applied to the main brake bolt, so don’t grease this part of the threads or inside the mounting bolt (where the mating threads are).
- To prevent rusting and ensure adequate tightening, do grease the part of the main brake bolts that will be inside the fork/frame, and the outside surface of the brake attaching bolts/nuts.
- Read the brake instructions to learn how the manufacturer intended the spacers and washers to be placed on the fork and frame. Then, try fitting them on your fork and frame that way. Sometimes a fork or frame will require you to do it differently. The goal is to provide a secure brake mounting point so it stays tight indefinitely.
- Make sure there’s adequate clearance for the brakes to operate. For example, sometimes you may need to add a spacer to clear certain headset lower cups. Make sure the brake doesn’t bump into anything when it closes and opens.
- Put the brakes in the fork and frame and barely tighten them in place. Close the brakes by squeezing them against the rims with your hands and check if the brake shoes hit the rims squarely on the braking surfaces. If not, loosen and move the brake shoes so that they line up with the rim braking surfaces (front and rear brake).
- Now, while holding each brake closed, firmly tighten the attaching bolts so that the brakes are fully tightened to the fork and frame. As long as the wheels are true and centered in the frame and fork, this step centers the brakes to the wheels, too.
Prepare the Brake for Final Adjustment
We won’t finish the brake adjustment until the cables and housing are installed. To make that final adjustment easy, here are a few steps to take now.
- Aligning the brake pads with the rim braking surfaces is one of the challenging parts of brake adjustment. For now, squeeze the brakes and check how well the pads line up. Sight from the sides, looking straight at the pad and braking surfaces and move the pads to make sure they’re centered and not too high or too low. Snug them so they stay put.
- Also look from the front (front brake) and from the back (rear). Move the pads so that they strike the rim flat and not at an angle (either up or down). Again, snug them so they stay put.
- Being sure to keep it off the brake pads and rims, apply a little drip or spray lube to the brake pivots and quick release mechanism.
- Unscrew the brake adjusting barrel a short amount and apply oil or grease to the threads and thread the adjuster back in to spread the lube and coat all surfaces.
- After letting the lube penetrate a bit, wipe off the excess.
That’s it for this week. Next, we’ll install the derailleurs! As always, be sure to share your brake installation tips and tricks in the Comments below the Newsletter version of this article.