Bike Brakes
Brakes are the one system where a mistake has immediate consequences, so these guides are written to be checked rather than skimmed. Every adjustment here ends with a test you should perform before riding.
The guides cover both rim and disc brakes, because the symptoms overlap but the fixes rarely do. Rubbing, squealing, a lever that reaches the bar and pads worn past their limit all get separate treatment.
What you'll learn
- Set pad clearance and alignment on rim and disc brakes
- Diagnose whether a problem is the pads, the cable, the rotor or the wheel
- Replace worn pads before they damage the rim or rotor
- Fix rubbing and squealing without introducing a new problem
- Run a new brake cable and housing so the lever feels sharp again
- Decontaminate a rotor properly, and know when pads cannot be saved
Guides in this topic
- How to Adjust Bike Brakes (Rim & Disc)
Adjust bike brakes properly: set pad height and toe-in, centre the caliper, and get cable tension right so the lever bites where you want it to.
- How to Tighten Bike Brakes
Fix a spongy brake lever that pulls too far: use the barrel adjuster first, the cable anchor bolt second, and know when the real problem is worn pads.
- How to Fix Bike Brakes: Symptom Guide
Diagnose bike brakes by symptom: squealing, rubbing, weak stopping, sticking levers and uneven pads, each with the actual cause and the fix.
- How to Adjust Disc Brakes on a Bike
Stop disc brake rub for good: centre the caliper, set mechanical pad clearance, check the rotor is straight, and know what only bleeding will fix.
- How to Loosen Bike Brakes That Drag
Back off brakes that rub or grab too early: use the barrel adjuster, check the caliper is centred, and find out why they went tight in the first place.
- How to Replace Bike Brake Pads
Replace rim and disc brake pads: wear limits, matching the right compound, setting toe-in, and bedding new pads in so they stop properly from day one.
- How to Clean Bike Brake Rotors
Clean disc brake rotors with isopropyl alcohol, find where the contamination came from, and know when the pads have to be replaced rather than cleaned.
- How to Replace a Bike Brake Cable
Fit a new brake inner wire and housing: cut housing cleanly, seat the ferrules, route it without kinks, and set tension so the lever feels sharp again.
Common questions
How do I know when my brake pads need replacing?
Rim pads are done when the grooves disappear. Disc pads are done at about 0.5 mm of friction material remaining, or when the manufacturer's minimum total thickness is reached. Replace them in pairs.
Why do my brakes squeal?
On disc brakes, usually contamination of the pads or rotor, which is why degreaser must be kept away from them. On rim brakes, usually pad alignment or a dirty braking surface.
Is a spongy brake lever dangerous?
It means the system is not transmitting your input properly. On cable brakes it is usually compressed housing; on hydraulics it means air in the line. Either way, do not ride until it is fixed.
Related topics
- Tires and wheels
Fix flats, change tires and tubes, patch punctures, repair a tubeless setup and true a buckled wheel — with the pressures and wear limits that matter.
- Cleaning and tune-ups
Wash your bike without forcing water into the bearings, and work through a full home tune-up checklist that finds problems before they leave you walking.