Disconcerting Disc Brake Noise

[unterhausen]

Originally Posted by XXtwindad

[/B]

I have the GRX.

This is your problem. I'm serious. Unfortunately I am not sure of the fix, but I know a lot of GRX are awaiting warranty from Shimano

[joosttx]

Originally Posted by unterhausen

This is your problem. I'm serious. Unfortunately I am not sure of the fix, but I know a lot of GRX are awaiting warranty from Shimano

Yep

[XXtwindad]

Originally Posted by unterhausen

This is your problem. I'm serious. Unfortunately I am not sure of the fix, but I know a lot of GRX are awaiting warranty from Shimano

I don’t know whether to be elated or upset that the fix is so easy. I didn’t know anything about warranty issues. I’ll definitely have to look into it, though. Thanks for the heads up. My bike was built around the GRX crank, so there’s no changing that, I don’t think. Can’t say it’s the most aesthetically appealing crank. But I really like the ergonomics of the hoods, so that’s a big plus.

[eddief]

Rotors? Calipers? which?

[Pinned]

Which GRX components are awaiting warranty? I haven't heard that, nor has it been my experience. GRX 800 brakes + XT Rotors are a great combo that have been powerful and quiet for me, even better than my Dura Ace.

Shimano offers a metallic and a resin brake pad - the metallic can get noisy and will tend to when it gets a bit glazed over or contaminated.

If you haven't hit the rotors and pads with a light sanding + rubbing alcohol it's worth a shot. Otherwise, you may want to replace the pads.

[SlowPokePete]

When I replaced the pads on my Ultegra 8020 with metallic pads (which I've always used for longevity) the noise was horrible.

Switched to resin and "poof" the squealing pig was gone.

I would definitely give that a try.

SPP

[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).

[fignon's barber]

I had this squealing issue on my Orbea Terra with Ultegra disc about a year and a half ago. Tried cleaning/pads, etc. Drove me crazy. After much time on my workstand, I found the problem: every time I applied the brake, a tiny puff of hydro oil escaped from around the bleed screw on the caliper. I called a friend who was a shimano rep at the time. He said it was not uncommon and had me take it to the LBS and had the caliper replaced within a week under warranty. It's worked flawlessly since.

[joevers]

Originally Posted by fignon's barber

every time I applied the brake, a tiny puff of hydro oil escaped from around the bleed screw on the caliper. I called a friend who was a shimano rep at the time. He said it was not uncommon and had me take it to the LBS and had the caliper replaced within a week under warranty. It's worked flawlessly since.

While I haven't yet seen it on the road side, the lower end Shimano mtb brakes do this quite a bit. Shimano always will warranty and if not, they're only like 35$ to replace.

Also! If you haven't, bedding in your pads right will do quite a bit to preventing future braking noise. Every time you replace or resurface (sandpaper) pads or rotors, go spin around for 5-10 mins and bed them in intentionally.

But, as others have said I'm yet to have a truly silent disc brake. DA is pretty close, but still squeals on heavy descending. Sram road is last place.

[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

[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.