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I ride a Rabeneick TS5 2017 Alfine 8, bought in 2018, with about 5000km on it (mostly commuting on asphalt, in all weather (mostly dry), some easy forest trails). It has BR-M395 hydraulic disk brakes with resin pads, with BL-M395 levers and SM-RT54-S 160mm rotors, vertical dropouts, a bolt-on-axle hub dynamo (probably DH-3D37-NT) in the front, Alfine 8 IGH in the back. I frequently experience disk rubbing (both rhythmic and continuous) on both wheels. I usually managed to fix it by re-centering/adjusting the brakes and/or bending the rotors by hand, but after braking hard the noise often returns.

It got continuously more complicated to adjust, until a while ago I was unable to make the front brake silent, so I brought the bike to a LBS, who installed new pads. It was fine at first, but after a ride the noise returned. Being fed up (and also because the LBSes here are ridiculously expensive), I bought new rotors and the tools to install them. It took ages to adjust the wheel, brake, and rotor to make them run silently.

Today I got a flat and had to take off the front wheel to take out the tube and submerge it in water to find the whole. Patching it and putting it all back together was easy enough, but the brake was (of course) misaligned again and I again had to fiddle forever to adjust it properly.

So the questions are - do all (hydraulic) disk brakes need that much care? Is just this model particularly bad and more expensive ones are more reliable? Do I need to replace the brake itself (rather complicated because of the hydraulics)? Should I just ignore the noise? Am I doing something wrong? Should disk brakes only be used with thru-axles as the wheel position is fixed? Just as an example, the Surly Troll "expedition touring" bike has vertical dropouts and disk brakes too. If you get a flat in the middle of nowhere and had to take a wheel off to patch/replace the tube, how would you re-adjust the brake? Sounds like a nightmare!

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  • Do you have quick release or through axles?
    – gschenk
    Jun 28, 2020 at 21:09
  • This could be caused by a sticky piston. Refer this question, but use Mineral oil not DOT fluid on your brakes.
    – mattnz
    Jun 28, 2020 at 22:04
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    @gschenk Neither - the axle is a fixed part of the hub, you slide it into the open dropout and screw on nuts on both sides.
    – Erlkoenig
    Jun 29, 2020 at 4:20
  • @mattnz I don't think there's a sticky piston, as they both move properly when pulling the brake.
    – Erlkoenig
    Jun 29, 2020 at 4:21
  • Pressure from lever easily overcomes any friction in the pistons when braking, if the friction is a bit too high, they retract until the pressure is off the pad, but not all the way. Its worth seeing if a clean helps.
    – mattnz
    Jun 29, 2020 at 21:42

1 Answer 1

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Noise after hard braking is normal. The rotor heats up and warps slightly.

When you got rubbing after reinserting the wheel, that shows you didn't align the wheel correctly. You need to be applying as much downwards force as possible while tightening the QR in order to seat the axle in the dropouts. The one-sided force from tightening a QR skewer tends to twist the wheel askew, so you need to be pushing down the whole time to counteract this force. You can practice this by repeatedly removing and reinserting the wheel: once you no longer get rubbing, your technique is spot on.

And yes, you should just ignore the occasional noise. There's no safety issue or anything, and unless you've already purchased $1200 CeramicSpeed jockey wheels, there's no point chasing the performance benefits of eliminating minor rubbing either.

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  • Thanks for the info. I forgot to mention the bike doesn't have QR's but bolt-on axles (added links in the question). Is the assembly procedure the same for these? Can I just have my friend sit in the saddle while I tighten the axle nuts?
    – Erlkoenig
    Jun 28, 2020 at 19:30
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    @Erlkoenig You don't need a friend to sit in the saddle no. Usually, all you need is to push down with your upper body weight and one arm while you operate the axle with the other arm. Make sure you tighten both sides evenly and a little at a time.
    – MaplePanda
    Jun 28, 2020 at 20:02
  • Okay thanks! I'll try that next time I have to re-adjust the brake or take off the wheel. If that doesn't help, I'll check for sticky pistons as @mattnz commented.
    – Erlkoenig
    Jun 30, 2020 at 6:04

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