Squealing Ultegra disc brakes

Ask for advice or share your fettling tips
mlan
Posts: 14
Joined: Fri Oct 05, 2018 17:16 pm

Squealing Ultegra disc brakes

Postby mlan » Mon Oct 08, 2018 12:00 pm

Hi all,

I've been having an ongoing issue with extremely noisy and ineffective brakes.

I got the bike in December and rode through the winter with no issues what so ever. It then came to May where I tried to take the pads out to replace them, only to discover the pins holding the pads in place were seized. I took the bike to the bike shop where they drilled out the pins, and replaced the pads. After this I had a couple of silent rides before the brakes started squealing (in the dry) and the front especially became fairly ineffective at stopping. I went back to the bike shop where they de-glazed the pads however this didn't stop it.

By this point I moved and so went to the new local bike shop. They took one look and said that my discs and pads were contaminated and needed a good clean. I went away and used some disc brake cleaner and replaced the pads. I did one ride and then at the start of the second ride the noise was back.

My next move was to replace the discs since I assumed they were't clean enough even after the deep clean. With new pads and new discs after one ride with the brakes working perfectly, the noise was back at the start of the second.

Frustration was getting the better of me and everything I had found online seemed to say they were contaminated.

I went back to the bike shop and told them to do whatever it takes to fix it. They cleaned the calipers and put on new disc and pads but it was exactly the same story - first ride is fine, second ride noisy.

After even more searching I found an article saying that road disc brakes need to be carefully bedded in. Up until this point I had assumed that the first couple of rides bed them in as I go (as had been the case with all other bikes, and with this one when I got it). I sanded off the pads a bit and wiped down the discs and followed a bedding in process of getting up to speed and then gradually slowing to a walking pace. After repeating this many times the noise went away and the brakes appeared to be working perfectly. However after a couple hours I went to check and low and behold the noise and ineffectiveness was back...

By this point I was stumped:
- Two sets of new rotors and pads surely wouldn't be contaminated to that extreme on a single ride, and why would the noise develop over night rather than at the moment of contamination?
- As for bedding in I didn't do a proper bedding in when I first got the bike and having asked the LBS they said it shouldn't be a problem.
- The other thought was the drilling could have caused a leak, however the LBS couldn't find anything and in the 5 months since then I haven't had a loss of pressure from the hydraulics.
- A loose bolt or mounting plate also doesn't seem to be the issue, why would the noise only start on ride two, and go away after my bedding in attempt?

Sorry for the long post but both the LBS and I are stumped so was wondering if anyone had experience/suggestions?

Some more technical spec:
Bike: Canyon Ultimate SL Disc 8.0
Brakes: Shimano Ultegra BR-R8070
The discs and pads I've been using are the ICE rotors and the road pads with the little plastic fins on.

Thanks in advance!

User avatar
DeVlaeminck
Posts: 5300
Joined: Sat Sep 21, 2013 20:34 pm

Re: Squealing Ultegra disc brakes

Postby DeVlaeminck » Mon Oct 08, 2018 12:29 pm

Assuming you don't spray lube or some kind of cleaning product on the bike?

Do you drag the brakes on descents because that can glaze the pads.
Holbrook Sports FC Women - sign for us

mlan
Posts: 14
Joined: Fri Oct 05, 2018 17:16 pm

Re: Squealing Ultegra disc brakes

Postby mlan » Mon Oct 08, 2018 12:52 pm

Thanks for the reply!

Definitely no lube or cleaning product on them - the most recent set of rotors I didn't re-lube the chain or clean the bike before using.

I don't consciously drag the brakes on descents, and where I live is fairly flat. Also given the brakes were fine for the first 5 months I can't see why they would start glazing now.

The fact the noise seems to develop once the brakes cool down (i.e. left over night) and only go temporarily after working hard to heat them up during my attempted bedding in does seem to suggest some kind of glazing is happening.

mamil314
Posts: 1128
Joined: Tue Mar 24, 2015 17:48 pm

Re: Squealing Ultegra disc brakes

Postby mamil314 » Mon Oct 08, 2018 13:37 pm

Pad glazing is caused by prolonged and weak braking. Smash those brakes before turns and let them cool between. This is the way to bed them in, too. Also, organic pads tend to squeal less than metallic ones

david7m
Posts: 527
Joined: Wed May 23, 2018 08:26 am

Re: Squealing Ultegra disc brakes

Postby david7m » Mon Oct 08, 2018 13:43 pm

Take the pads out, remember which way they were otherwise you'll need to bed them again, work in washing liquid and rinse. For the discs, I use Pagid Brake Cleaner. Dont wash the bike with car shampoos as they normally contain products to enhance the shine of paint work which isnt good for brake surfaces.
Dave

mlan
Posts: 14
Joined: Fri Oct 05, 2018 17:16 pm

Re: Squealing Ultegra disc brakes

Postby mlan » Mon Oct 08, 2018 13:46 pm

mamil314 wrote:Pad glazing is caused by prolonged and weak braking. Smash those brakes before turns and let them cool between. This is the way to bed them in, too. Also, organic pads tend to squeal less than metallic ones


Would you suggest sanding the pads a bit, then finding a road to get up to speed on then slamming on the brakes a few times?

Given they were quiet immediately after my past attempt, but after a few hours left alone became noisy again would the same thing happen again?

david7m
Posts: 527
Joined: Wed May 23, 2018 08:26 am

Re: Squealing Ultegra disc brakes

Postby david7m » Mon Oct 08, 2018 13:47 pm

Do you keep putting same brand and compound in? If so, how about trying a different brand as it seems odd they go noisy when they havent been contaminated.
Dave

mlan
Posts: 14
Joined: Fri Oct 05, 2018 17:16 pm

Re: Squealing Ultegra disc brakes

Postby mlan » Mon Oct 08, 2018 13:56 pm

I've been using the Shimano pads and discs, identical to the ones supplied with the bike. They definitely can't be contaminated given two brand new sets (pads and discs) did the same thing after one ride. Does anyone know if Canyon specifically bed in the pads before they send them, as this is the only difference I can think of between new from them and new from the LBS?

User avatar
Franco di Banco
Posts: 390
Joined: Thu Oct 04, 2018 17:38 pm

Re: Squealing Ultegra disc brakes

Postby Franco di Banco » Mon Oct 08, 2018 13:58 pm

My 105 discs have always squealed. Usually if I don't totally dry them off after a wet ride. They can also squeal if the get wet during a ride.
I live with it, but as I do a lot of riding on narrow country lanes a bit of squeal is useful as a warning to pedestrians!!!

mlan
Posts: 14
Joined: Fri Oct 05, 2018 17:16 pm

Re: Squealing Ultegra disc brakes

Postby mlan » Mon Oct 08, 2018 14:05 pm

The problem with my squeal is that it's not only absolutely ear-splitting (warns not just those on the road but also the entire town) but also that the brakes feel like they have no bite. My current lean is that it's a case of glazed pads but given that after a specific de-glazing ride the noise was back after a couple hours I'm stumped!

Svetty
Posts: 1896
Joined: Fri Jun 13, 2008 16:29 pm

Re: Squealing Ultegra disc brakes

Postby Svetty » Mon Oct 08, 2018 14:12 pm

Squealing might indicate vibration. Are the caliper mounting bolts tight? Is the piston:pad interface clean and dry? Do the pistons move in and out smoothly?
FFS! Harden up and grow a pair :D

HaydenM
Posts: 2638
Joined: Mon Feb 08, 2016 09:03 am

Re: Squealing Ultegra disc brakes

Postby HaydenM » Mon Oct 08, 2018 14:13 pm

Franco di Banco wrote:My 105 discs have always squealed. Usually if I don't totally dry them off after a wet ride. They can also squeal if the get wet during a ride.
I live with it, but as I do a lot of riding on narrow country lanes a bit of squeal is useful as a warning to pedestrians!!!


I was going to say, having had discs on mtb and road for years, some bikes squeal and others don't, I just ignore it. The squealing is sometimes caused by pads vibrating in the calipers, some people suggest putting a very small amount of copper grease on the back of the pads between the piston and the pad but I haven't tried it and would hate for it to somehow contaminate the pad in use. What is concerning is that you say they are losing power rather than just noise? Might be piston seals leaking very slightly?

mlan
Posts: 14
Joined: Fri Oct 05, 2018 17:16 pm

Re: Squealing Ultegra disc brakes

Postby mlan » Mon Oct 08, 2018 14:17 pm

Svetty wrote:Squealing might indicate vibration. Are the caliper mounting bolts tight? Is the piston:pad interface clean and dry? Do the pistons move in and out smoothly?


Calipers were checked and cleaned by LBS before most recent set of pads were fitted. We discussed vibration but that doesn't seem to explain why they would be silent for the first ride, or at the end of the 'bedding in ride' - I would have thought the noise would be there from the beginning if it was vibration?

mlan
Posts: 14
Joined: Fri Oct 05, 2018 17:16 pm

Re: Squealing Ultegra disc brakes

Postby mlan » Mon Oct 08, 2018 14:23 pm

It's a combination of both - the squeal isn't a wet brake squeal like I've had with wet mountain bike brakes, it's a real howl. As for the power, with the front brake fully on I can (very noisily) push the wheel around which means when actually riding its fairly ineffective.

The brakes don't feel spongy at all, and I would have thought if stuff can leak out then air would have also leaked in?

david7m
Posts: 527
Joined: Wed May 23, 2018 08:26 am

Re: Squealing Ultegra disc brakes

Postby david7m » Mon Oct 08, 2018 14:25 pm

They sound absolutely shite if you can move it by hand, and I wouldnt use it on the road until its fixed.
Do you have any friends/clubs locally where you can compare to others with same set up? Maybe switch some parts to isolate.
Dave

cougie
Posts: 22419
Joined: Wed Apr 21, 2004 22:34 pm

Re: Squealing Ultegra disc brakes

Postby cougie » Mon Oct 08, 2018 14:35 pm

I thought discs were meant to be progress ?

They sound like a nightmare.

HaydenM
Posts: 2638
Joined: Mon Feb 08, 2016 09:03 am

Re: Squealing Ultegra disc brakes

Postby HaydenM » Mon Oct 08, 2018 14:39 pm

cougie wrote:I thought discs were meant to be progress ?

They sound like a nightmare.


They are progress.

Slowbike
Posts: 8249
Joined: Wed May 02, 2012 09:26 am

Re: Squealing Ultegra disc brakes

Postby Slowbike » Mon Oct 08, 2018 14:44 pm

HaydenM wrote:
cougie wrote:I thought discs were meant to be progress ?

They sound like a nightmare.


They are progress.

Which direction?! ;)

HaydenM
Posts: 2638
Joined: Mon Feb 08, 2016 09:03 am

Re: Squealing Ultegra disc brakes

Postby HaydenM » Mon Oct 08, 2018 14:47 pm

Slowbike wrote:
HaydenM wrote:
cougie wrote:I thought discs were meant to be progress ?

They sound like a nightmare.


They are progress.

Which direction?! ;)


You make much better progress into the floor when you lock up the front wheel... :lol:

Kajjal
Posts: 3391
Joined: Tue Aug 27, 2013 16:37 pm

Re: Squealing Ultegra disc brakes

Postby Kajjal » Mon Oct 08, 2018 14:58 pm

Your problem sounds like contamination of the pads and rotors.

To remove the contamination you need to use disc brake cleaner and white kitchen roll. Clean the whole of the affected rotor until the white kitchen roll stays white. This can take a few attempts and also don't forget the thin edge on the top of the rotor. The pads just need to go in the bin and be replaced by new ones. Once oil etc. soaks into pads you are unlikely to win by cleaning them. Before fitting the pads carefully clean the brake calliper inside and out with disc brake cleaner to remove any trapped oily muck and gunk. Again be thorough as this can take a while.

Likely causes of contamination are too much oil on the drivetrain (It needs to have very little oil on it, wipe all excess off with kitchen roll.), a dirty gunked up drive train, riding through something like oil, getting some kind of oily muck into the calliper so it just contaminates whatever you do until the calliper is cleaned out or when cleaning / maintaining the bike getting oil on the rotor or calliper.

I have three bikes with disc brakes and the main cause of contamination was too much oil on the chain. Since then they have all been fine, with my newest bike never having had any problems.


Return to “Workshop”

Who is online

Users browsing this forum: No registered users and 17 guests