Disconcerting Disc Brake Noise

[XXtwindad]

On long, winding descents I’ve been having some issues with a really shrill sound with my disc brakes. Disconcerting to say the least. I’m sure this is a fairly common problem. Easy fix? (Besides riding rim brakes. I have a few of those. Thx)

[Ken Robb]

Service advisor at BMW Dealer: "They all do that."

[yinzerniner]

Originally Posted by XXtwindad

On long, winding descents I’ve been having some issues with a really shrill sound with my disc brakes. Disconcerting to say the least. I’m sure this is a fairly common problem. Easy fix? (Besides riding rim brakes. I have a few of those. Thx)

Easy fix - brake less.


But for real without more description it's tough to nail it down. Might be as easy as cleaning rotors with rotor-specific degreaser, sanding down pads and bedding them again - 10 min fix. Or it could involve trying different rotor and pad combinations.

One thing I've noticed - the newest Shimano road rotors brake really well but they're loud AF, and any hint of contamination makes them louder still. Thinking of going back to MTB centerlock rotors.

[XXtwindad]

Originally Posted by yinzerniner

Easy fix - brake less.


But for real without more description it's tough to nail it down. Might be as easy as cleaning rotors with rotor-specific degreaser, sanding down pads and bedding them again - 10 min fix. Or it could involve trying different rotor and pad combinations.

One thing I've noticed - the newest Shimano road rotors brake really well but they're loud AF, and any hint of contamination makes them louder still. Thinking of going back to MTB centerlock rotors.

I have the GRX.

[eddief]

and when mine made noise it was obnoxious. thought i'd fixed by cleaning pads and rotors. but i could apply brakes slowly no noise, but at the very end of the stop they'd squeal like crazy. cleaned rotors, got new pads, bedded them in and the noise was gone.

cleaning works sometimes but the pads can get goop on em you can't get out. so nice when they work and mostly they do.

[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

[madsciencenow]

I’d like to hear more about this warranty issue as I have exactly one ride on my GRX groupo and like Josh my bike is centered around this crankset.


Sent from my iPhone using Tapatalk

[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.