New brake pads that feel weak, grabby, or squeal on every stop almost always mean one thing: they haven't been bedded in properly. Bedding in transfers a thin, even layer of pad material onto the rotor, and skipping it is the single most common reason new pads underperform. Here's how to do it right.
Why Bedding In Matters
A brand new pad and rotor surface are both effectively bare. Braking power comes from an even transfer layer of pad material building up on the rotor, not from the pad and rotor metal contacting directly. Skip the bedding process and that transfer layer forms unevenly, which is exactly what causes the squealing, pulsing, or weak initial bite that makes new pads feel worse than the old ones they replaced.
Before You Start
Clean the rotors thoroughly with isopropyl alcohol or a dedicated disc brake cleaner, never solvents that leave residue. Once clean, avoid touching the rotor surface or the new pad material with bare fingers; skin oil contaminates both and undoes the cleaning step. Find a flat, safe stretch of pavement or fire road away from traffic, since you'll need room to brake repeatedly without stopping.
The Bed-In Procedure, Step by Step
- Get up to a moderate speed, roughly 15 to 20 km/h, staying seated on the bike.
- Apply one brake firmly and evenly, slowing to walking pace without coming to a complete stop or locking the wheel.
- Release and repeat this cycle 10 times on that brake.
- Increase to a faster speed, roughly 25 to 30 km/h, and repeat the slow-down cycle 10 more times on the same brake.
- Switch to the other brake and repeat the entire sequence.
- Let the brakes cool completely before riding normally. Riding hard on hot, freshly bedded pads can undo the transfer layer you just built.
How to Tell It's Done Right
A properly bedded brake should feel firm at the lever, bite progressively rather than grabbing suddenly, and stop the bike with real power without excessive noise. Some light noise during the bedding process itself is normal; what you're checking for is quiet, consistent performance once you're done, not silence during the procedure.
Troubleshooting: Still Squealing After Bedding
If pads are still squealing after a proper bed-in, the cause is usually one of these:
Contamination. Chain lube, degreaser overspray, or even fingerprints on the rotor or pad surface will cause persistent noise no matter how many times you repeat the procedure. Clean both surfaces again and rebed.
Wrong pad compound for the conditions. Some compounds are simply noisier than others, particularly in wet weather common around Vancouver and Squamish. If you've confirmed clean rotors and a correct bed-in and noise persists, the compound itself may not suit your riding. Our sintered vs organic pads guide covers how compound choice affects noise, bite, and wet-weather performance.
Glazing from overheating. Long descents that overheat the pads can glaze the surface, which reduces friction and often causes noise. A glazed pad usually needs to be lightly sanded or replaced rather than rebedded.
When to Bed In Again
Any time you install new pads or a new rotor, bed in again, even if you're reusing a pad that was previously bedded to a different rotor. If your bike goes through deep mud, standing water, or gets sprayed with degreaser during a wash, check for contamination before assuming a rebed is needed; cleaning may be enough on its own.
FAQ
How long does it take for brakes to be bedded in?
The procedure itself takes a few minutes per brake. Full performance typically settles in over the first several rides as the transfer layer continues to even out under normal use.
What is the 30-30-30 rule for bedding in brakes?
It's a shorthand some riders use: roughly 30 stops from a moderate speed, allowing the brakes to cool for about 30 seconds between hard efforts, repeated for both brakes. The exact numbers vary by brand; following your brake manufacturer's specific procedure (like the one above) matters more than any fixed rule.
Do you need to rebed pads after changing rotors?
Yes. Even if the pads themselves are already bedded, a new rotor surface hasn't built up a transfer layer yet, and mismatched surfaces cause the same noise and weak-bite symptoms as skipping the process entirely.
Do brake pads need to be bedded in if they're not new?
No, only new pads or new rotors need the full procedure. Pads that have already been bedded and are performing well don't need to be rebedded unless they've been contaminated or the rotor has changed.
Need a Hand With Your Brakes?
If you're not sure which pad compound is on your bike, our Shimano brake pad compatibility chart can help you confirm before you buy a replacement. Browse our full MTB brake pad selection, or bring your bike into Dunbar Cycles in Vancouver or Corsa Cycles in Squamish and we'll bed in new pads correctly the first time.
