Fitted new organic pads and new rotors on a hydraulic setup. Braking power is fine but there is a loud howl on the front, especially at low speed and when damp. I bedded them in with about twenty hard stops from 25 km/h like the instructions said. Does this settle down or have I contaminated something already?
Bed them in properly and then stop listening to them for two weeks. Half of all brake noise threads are people who have started paying attention to a noise their bike always made.
New rotors sometimes ship with a factory coating. A wipe with isopropyl before the first ride is a thirty second job that prevents a fortnight of noise.
I have unwrapped rotors with a genuinely oily film on them. Always clean them.
One thing that is not normal: howl plus noticeably weak braking. If the power is there you are almost certainly fine.
Do not spray anything at the rotor. Every week somebody tries to solve brake noise with a lubricant and buys new pads.
@chain_wear_chase · 2mo ago · 4 replies
It usually settles, but there are two causes worth separating because only one of them goes away.
If it is a low frequency howl that changes with speed and is worse when damp, that is normally bedding-in not being finished. Twenty stops from 25 km/h is fewer than most people think. I do about thirty stops from a higher speed, never coming to a complete stop, with cooling time between sets. Give it two more rides.
If it is a constant loud squeal from cold that never varies, suspect contamination. Chain lube overspray, a fingerprint, any oil at all is enough. Clean the rotor with isopropyl and a clean rag, then sand the pad faces lightly on flat coarse paper. If the pads actually soaked up brake fluid or lube they are finished and no cleaning brings them back.
Also check caliper alignment. A slightly skewed caliper makes an intermittent honk that people spend weeks blaming on pads: loosen the two mounting bolts, hold the lever hard, tighten alternately.
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@couchto5kagain · 2mo ago
It is definitely worse damp and quieter after ten minutes of riding, so probably bedding.
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@chain_wear_chase · 2mo ago
Then just ride it. Organic pads go quiet once they are properly in, and a week of normal use does most of the work.
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@lowtech_lior · 2mo ago
Worth saying too: some rotor and pad combinations howl in the wet forever. That is not a fault, it is a material choice.
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