How To Adjust Cable Activated Disc Brakes | Maintenance Monday, by GCN Tech on YouTube. 4 min 31 s.
- Video length
- 4 min 31 s
- Time to do it
- 15 minutes
- Difficulty
- Easy
- Steps
- 8
What you need
Steps
Put the bike in a stand or flip it so you can spin the wheel freely. Check that the wheel is seated fully in the dropouts before you touch the brake.
Squeeze the brake lever and watch the caliper. If the lever pulls close to the bar, the cable has slack and the pads are worn or the barrel adjuster is wound in.
Turn the barrel adjuster on the caliper or lever out a few turns to take up slack. Spin the wheel and listen for rubbing.
If the adjuster runs out of thread, loosen the cable anchor bolt on the caliper arm with your hex key. Pull the cable taut by hand and retighten the bolt.
Loosen the two caliper mounting bolts slightly so the caliper can move side to side. Squeeze the lever hard to let the caliper self-centre over the rotor, then tighten the bolts.
Spin the wheel again. Look through the caliper slot and check the gap between each pad and the rotor is roughly even on both sides.
If one pad still rubs, turn the fixed pad adjuster on the inboard side in small clicks until the rotor runs clear.
Squeeze the lever a few times and check it feels firm, with the pads biting before the lever reaches the bar. Test the brake at walking pace before you ride.
Tips and common mistakes
Turn adjusters a quarter turn at a time and spin the wheel after each change, so you do not overshoot and cause drag.
If the pads are worn past the wear line, replace them instead of winding the adjuster all the way out.
Keep oil and grease off the rotor and pads, and clean them with isopropyl alcohol if you touch them.
Check the brake again after the first few rides, since new cables stretch and pads bed in.
Questions
Do I need to remove the wheel to adjust the brakes?
No. You can do the whole job with the wheel in place, as long as you can spin it freely. Removing the wheel is only useful if you want to inspect the pads closely.
Why does my disc brake still rub after adjusting?
The caliper is probably not centred or the rotor is slightly bent. Loosen the mounting bolts, squeeze the lever to centre the caliper, retighten, and straighten a bent rotor with a clean adjustable spanner.
How do I know when the pads need replacing?
Look at the pad material through the top of the caliper. If it is thinner than about 1 mm above the backing plate, or the adjuster is nearly maxed out, fit new pads.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
