How to adjust the front brake - Qlife ebike, by Qlife bike on YouTube. 1 min 13 s.
- Video length
- 1 min 13 s
- Time to do it
- 15 minutes
- Difficulty
- Easy
- Steps
- 10
What you need
Steps
Lift the front wheel off the ground and spin it. Squeeze the front lever and watch where the pads meet the rotor. Note whether the brake rubs, feels spongy or pulls the lever too far.
Check the brake pads first. Look through the caliper slot and replace the pads if less than about 1 mm of friction material is left. Worn pads cause most adjustment problems.
Clean the rotor with isopropyl alcohol on a rag. Oily or greasy rotors squeal and grab, and no amount of adjustment fixes that.
Centre the caliper. Loosen the two caliper mounting bolts about half a turn so the caliper can move, then squeeze and hold the front lever.
Retighten both mounting bolts evenly while the lever is still held, then release the lever. This lines the caliper up with the rotor.
On a cable brake, loosen the cable clamp bolt on the caliper arm with a 5 mm hex key. Pull the cable snug by hand and retighten the bolt.
Turn the inner pad adjuster screw on the caliper in until the pad just touches the rotor, then back it out a quarter turn. Spin the wheel to check for rub.
Fine tune the lever feel with the barrel adjuster where the cable meets the brake lever. Turn it out to take up slack, and check that the lever does not reach the handlebar grip.
Spin the wheel again and listen. If the rotor still rubs in one spot only, it is probably slightly bent. Straighten it gently with a clean adjustable spanner or have a shop true it.
Test at walking pace. Push off and brake firmly with the front only, then both brakes. The front wheel should slow smoothly without grabbing or pulling to one side.
Tips and common mistakes
Never let oil or chain lube touch the rotor or pads, as it ruins braking power.
If the lever feels spongy on a hydraulic brake, do not open the system. Have a shop bleed it.
Tighten the caliper bolts a little at a time, alternating between them, so the caliper stays centred.
Recheck pad wear every few hundred kilometres, since ebike brakes wear faster than a normal bike.
Questions
Why does my front disc brake rub after adjustment?
The caliper is usually not centred or the rotor is slightly bent. Loosen the mounting bolts, hold the lever, retighten, then spin the wheel to check.
How do I know if my brake pads need replacing?
Look at the friction material through the caliper slot. If less than about 1 mm is left, or the pads look glazed or contaminated, fit new ones.
Can I adjust a hydraulic brake the same way?
You can centre the caliper and check pad wear the same way. Lever feel and sponginess are set by bleeding the system, which is best left to a bike shop.
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.
