Disconcerting Disc Brake Noise

[2metalhips]

I've been on GRX for over a year, all kinds of conditions, resin pads, 6 bolt rotors, dead quiet. Awesome brakes IME.

[Jaybee]

Originally Posted by 2metalhips

I've been on GRX for over a year, all kinds of conditions, resin pads, 6 bolt rotors, dead quiet. Awesome brakes IME.

My GRX is dead silent too, unless I splash some water or snow on the rotors. Then it squeals for maybe 1 good hard stop until the water cooks off and it's back to silent. Resin pads, both 6 bolt and center lock XT rotors.

[SoCalSteve]

Originally Posted by joevers

SwissStop organic pads are supposed to be the quietest pads you can get if you can get over the price. Current Shimano rotors tend to warp a little under heavy braking and will sometimes squeal for a bit until they cool down (usually only 5-10 seconds IME).

Swissstop pads and rotors here. Unless there is moisture, they are very, very quiet.

[yinzerniner]

Originally Posted by SoCalSteve

Swissstop pads and rotors here. Unless there is moisture, they are very, very quiet.

Have only heard great things about that combo, will probably try them out when the current set wears out.

And to the OP - big Youtube brother is listening, even all the way in the UK ....
https://youtu.be/JJSmNS51JqA?t=328

[MikeD]

Shimano J02A pads squealed. When they wore out, I replaced them with the newer J03A pads and no more squeal, except they still make scraping noises.

[XXtwindad]

Originally Posted by SoCalSteve

Swissstop pads and rotors here. Unless there is moisture, they are very, very quiet.

Thanks for all the tips and feedback. I’ll definitely look into these. Funny, there were many times while descending steep and twisty hills on rim brakes that I wished I had discs. Then you hear grinding noises like this and it gives you pause barreling down a hill at 40 plus mph. One longs for the simplicity of rim brakes.

Go figure...

[benb]

I have never cared about the noise... that is the sound of performance.

I'd start with making sure the calipers are well aligned.

But all this effort to make the brakes as quiet as possible distracts from the goals of making the braking the best it can be. Even just Shimano defaulting everything to the organic/resin pads all in the name of quiet.

If quieter is consistently a higher priority than performance rim brakes are still there.

[XXtwindad]

Originally Posted by benb

I have never cared about the noise... that is the sound of performance.

I'd start with making sure the calipers are well aligned.

But all this effort to make the brakes as quiet as possible distracts from the goals of making the braking the best it can be. Even just Shimano defaulting everything to the organic/resin pads all in the name of quiet.

If quieter is consistently a higher priority than performance rim brakes are still there.

Haha. I don’t like the noise at all. It’s extremely disconcerting. I’ll gladly switch to pads that mitigate the racket. But I’ll say this: between my i9 hubs and (currently) screeching discs, people have no problem hearing me coming. I’m like Radio Raheem.

[recarcar]

Originally Posted by benb

I have never cared about the noise... that is the sound of performance.

I'd start with making sure the calipers are well aligned.

But all this effort to make the brakes as quiet as possible distracts from the goals of making the braking the best it can be. Even just Shimano defaulting everything to the organic/resin pads all in the name of quiet.

If quieter is consistently a higher priority than performance rim brakes are still there.

I have had no drop in performance in going from metallic pads to resin. But I have had a huge reduction in the terrible screeching produced by the metallic pads in the wet. You can have performance and less noise. Quite glad that I can now go down smaller and quieter neighborhood streets in the rain without feeling like I'm disturbing the whole block or annoying/scaring nearby pedestrians

[BlueHampsten]

Still waiting for details on alleged warranty problems with GRX group set.

Is this for real or does someone find this funny?

[elladaddy]

Originally Posted by BlueHampsten

Still waiting for details on alleged warranty problems with GRX group set.

Is this for real or does someone find this funny?

This is the only recall info I could find:

https://bike.shimano.com/en-US/infor...-calipers.html

[davidb]

Two questions:
1) Were the pads bedded in per the manufacturer's instructions? It really makes a difference. No shortcuts just do what it says to do.
2) Has the frame/fork been faced? Many bicycles need it. Brakes will squeal and howl then when properly faced everything is quiet.

[Dave]

Don't know what the grx crank has to do with any of this, other than the +2.5mm chain line and and the FD made to go with it. If calipers are thought to be a problem, surely some higher level component would be compatible.

I'm using Campy rotors with Galfer and the Juin-Tech pads that came with my mechanically operated hydraulic calipers. Both are quiet.

I've got a grx crank too. It looks OK to me. I eliminated the +2.5mm chainline with spacing washers and pair it with SRAM force axs 12 speed. It all plays nicely together.

[vqdriver]

ime the 'system' has less to do with noise than pad/rotor combo. assuming the pads are clean and the system is otherwise working well, i'd try cleaning the rotors and scuffing up the pads a bit. then bed them in again.
if the same but on prolonged descents then i'd guess it could be heat build up. if the rotors are heat warping, then try finned rotors or bigger size. if the pads are glazing then try finned pads and/or a different compound.

fwiw, i've had great luck with swisstop green backed resin pads with xt finned rotors on sram road, shimano mtb, and tektro mtb.

[joevers]

Originally Posted by benb

I have never cared about the noise... that is the sound of performance.

I'd start with making sure the calipers are well aligned.

But all this effort to make the brakes as quiet as possible distracts from the goals of making the braking the best it can be. Even just Shimano defaulting everything to the organic/resin pads all in the name of quiet.

If quieter is consistently a higher priority than performance rim brakes are still there.

I don't know if I feel the same. I've found organic stop better on the road at the only real expense of ultimate power and pad wear. Unless it's very wet, I'd say my disc brakes are quieter than my rim brake set ups, both on carbon and alloy (but definitely carbon). I even prefer organic on my mtb, but the only riding I really do is cross country, no enduro or downhill stuff where I'm sure I would prefer metallic pads.

I'm glad you don't, really. But working at a shop the #1 reason people bring their disc brake set ups into the shop is for noise. Lots of people do mind noisy set ups, which I think is reasonable.

Originally Posted by vqdriver

ime the 'system' has less to do with noise than pad/rotor combo. assuming the pads are clean and the system is otherwise working well, i'd try cleaning the rotors and scuffing up the pads a bit. then bed them in again.

For sure agree, the lever and the caliper have virtually nothing to do with the noise. Just the pads and the rotor.