Disc vs rim brake pads: when to replace them
Brake pads are the one wear item where running them too long isn't just expensive — it's a safety issue. The good news is they're easy to check. Here's how to know when disc or rim pads are done.
Disc brake pads
Disc pads have a thin layer of friction material bonded to a metal backing plate. You're checking how much of that material is left.
- Replace when the pad material is down to about 1–1.5 mm (some brands mark a minimum). Below that you risk the metal backing contacting the rotor — which ruins the rotor and kills braking.
- Listen. A new squeal or a harsh grinding sound often means the pads are low or gone.
- Look. Pull the wheel and shine a light into the caliper, or peek through the top. If you can barely see friction material, it's time.
- Feel. Brake levers pulling closer to the bar, or weaker, vaguer braking, are late-stage warnings.
Rough mileage: anywhere from 2,000 to 6,000 km, but conditions dominate. Wet, gritty, and hilly riding can wear a set in a few hundred kilometres; dry flat riding can stretch them much further.
Rim brake pads
Rim pads press directly on the wheel's braking surface, so you can usually inspect them without removing anything.
- Replace when the grooves are gone. Most rim pads have molded grooves or a wear line; once the pad is worn flat to that line, replace it.
- Check for embedded grit and metal shards — these score your rims. Pick them out or replace the pad.
- Don't forget the rim itself. Rim brakes slowly wear the rim's braking surface too. Many rims have a wear indicator (a small dimple or groove); if it's gone, the rim needs attention.
Rough mileage: broadly similar to disc — roughly 2,000–6,000 km, heavily condition-dependent.
Why you shouldn't wait
Unlike a chain, brake pads don't just get expensive when ignored — they get dangerous. Worn-through pads mean longer stopping distances, damaged rotors or rims, and the occasional nasty surprise on a fast descent. Pads are cheap; rotors, rims, and crashes are not.
Make it a habit, not a guess
Because pad wear depends so much on weather and terrain, there's no clean "replace every X km" number — which is exactly why a quick visual check every few weeks beats waiting for the grinding noise. Tracking distance since your last pad change gives you a reminder to look before they're metal-on-metal. For the full picture, see our bike maintenance schedule by mileage.