Squealing Ultegra disc brakes

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Vino'sGhost
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Re: Squealing Ultegra disc brakes

Postby Vino'sGhost » Tue Oct 09, 2018 14:31 pm

HAHAHHA good spot imposter

keef66
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Re: Squealing Ultegra disc brakes

Postby keef66 » Tue Oct 09, 2018 15:52 pm

Ye gods! I can't keep up with his constantly changing identity. It's like Catch Me If You Can but without the confidence trickery, forgery, or Mr DiCaprio's charm.

I've stopped using copper goo on the brakes on cars. Modern braking systems don't require it / manufacturers advise against it. And there are better things to lubricate the moving parts.

It's still a good anti-seize for pedal and BB threads on a bike though.

FWIW the description of the pattern of the OP's problems does indeed suggest leaking pistons / repeated overnight contamination. I'd be curious to know if the bike shop which removed the stuck pins did anything to the pistons / seals in the process

Vino'sGhost
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Re: Squealing Ultegra disc brakes

Postby Vino'sGhost » Tue Oct 09, 2018 18:51 pm

keef66 wrote:Ye gods! I can't keep up with his constantly changing identity. It's like Catch Me If You Can but without the confidence trickery, forgery, or Mr DiCaprio's charm.

I've stopped using copper goo on the brakes on cars. Modern braking systems don't require it / manufacturers advise against it. And there are better things to lubricate the moving parts.

It's still a good anti-seize for pedal and BB threads on a bike though.

FWIW the description of the pattern of the OP's problems does indeed suggest leaking pistons / repeated overnight contamination. I'd be curious to know if the bike shop which removed the stuck pins did anything to the pistons / seals in the process


Given the quality of many bike shop mechanics I’ve come across I wouldn’t be surprised.

mlan
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Re: Squealing Ultegra disc brakes

Postby mlan » Tue Oct 09, 2018 20:01 pm

Looks like Plodder nailed it. Left some tissue in all day and took it out to find a fairly clear two piston pattern of leakage. So glad to have finally found the problem - it's been driving me nuts for ages! Will look into warranty but if it will take a while I'm just gonna buy new ones.

Thanks for all the help!

Vino'sGhost
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Re: Squealing Ultegra disc brakes

Postby Vino'sGhost » Tue Oct 09, 2018 20:06 pm

Sometimes the internet works

david7m
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Re: Squealing Ultegra disc brakes

Postby david7m » Tue Oct 09, 2018 20:09 pm

I love it when a plan comes together :D
Hopefully you can salvage the pads and rotors with fairy liquid and brake cleaner!
Dave

HaydenM
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Re: Squealing Ultegra disc brakes

Postby HaydenM » Wed Oct 10, 2018 10:21 am

HaydenM wrote:
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?


Imposter, I do like bashing him but it was actually me that first mentioned copper grease initially rather than BB/MM/KC, I have seen it recommended before but haven't tried it. The internationally renowned Halfords website suggests it for cars to stop brake squeal though...

I also suggested a correct diagnosis first because I am a genius (and have used disc brakes extensively) :wink:

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Veronese68
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Re: Squealing Ultegra disc brakes

Postby Veronese68 » Wed Oct 10, 2018 11:29 am

HaydenM wrote:Imposter, I do like bashing him but it was actually me that first mentioned copper grease initially rather than BB/MM/KC, I have seen it recommended before but haven't tried it. The internationally renowned Halfords website suggests it for cars to stop brake squeal though...

No help to the op but as a general comment on squealing discs and fixes from the automotive world, copper grease helps with vibration related squeals. It was certainly standard practice to put some on the back of car brake pads. The mechanics behind it should be the same with bicycle brakes, but I too would avoid it too due to the risk of contamination. Lockheed used to sell sticky pads that you could put on the back of pads that would dampen the vibration so reducing the squeal, not available now although some pads come with something on the back that serves a similar purpose. Again the theory is transferable although you would need something with heat resistant glue.
Another thing that helped with squealing (automotive) brakes is the groove you get in some pads. Apparently it helped get rid of a build up of dust so reduced noise. Not sure if that would work on bicycles brakes.
The change to asbestos free pads in the automotive world caused problems with more noise. Doubt you can buy bicycle pads with asbestos in them as they would be illegal in most of the western world.

Imposter
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Re: Squealing Ultegra disc brakes

Postby Imposter » Wed Oct 10, 2018 12:37 pm

HaydenM wrote: Imposter, I do like bashing him but it was actually me that first mentioned copper grease initially rather than BB/MM/KC, I have seen it recommended before but haven't tried it. The internationally renowned Halfords website suggests it for cars to stop brake squeal though...

I also suggested a correct diagnosis first because I am a genius (and have used disc brakes extensively) :wink:


Happy to concede all those points - even the genius one.. ;)

HaydenM
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Re: Squealing Ultegra disc brakes

Postby HaydenM » Wed Oct 10, 2018 12:41 pm

Imposter wrote:
HaydenM wrote: Imposter, I do like bashing him but it was actually me that first mentioned copper grease initially rather than BB/MM/KC, I have seen it recommended before but haven't tried it. The internationally renowned Halfords website suggests it for cars to stop brake squeal though...

I also suggested a correct diagnosis first because I am a genius (and have used disc brakes extensively) :wink:


Happy to concede all those points - even the genius one.. ;)


It's probably only people like me suggesting it time and time again on forums "I've heard it suggested, never tried it", I doubt anyone has tried it on bike brakes as it might lead to immediate death...

keef66
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Re: Squealing Ultegra disc brakes

Postby keef66 » Wed Oct 10, 2018 12:56 pm

[quote="Veronese68"
No help to the op but as a general comment on squealing discs and fixes from the automotive world, copper grease helps with vibration related squeals. It was certainly standard practice to put some on the back of car brake pads. Lockheed used to sell sticky pads that you could put on the back of pads that would dampen the vibration so reducing the squeal, not available now although some pads come with something on the back that serves a similar purpose.......[/quote]

OT, but curious... Faffing with cars I used copperslip on the backs of the pads for years. Partly because I'd been told it was a good thing, and once I had a tube I felt I should go on using it.

Now everything I read about vehicle disc brakes tells me not to. Some manufacturers supply 3 different kinds of goo with a caliper rebuild kit; something to lube the guide pins and their boots, a threadlock to keep them in place, and something else for the bits of the caliper which the ends of the pad backing plates are supposed to slide along. Never had a set of pads recommending anything copper based on the back, and seen several which have something stuck on the back already.

The makers of the alternatives say the copper 'grease' isn't a lubricant, attracts dirt, doesn't handle heat well, and can adversely affect ABS systems.

So is it obsolete as far as modern cars are concerned? And does it still have a place on classic cars?

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Veronese68
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Re: Squealing Ultegra disc brakes

Postby Veronese68 » Wed Oct 10, 2018 13:07 pm

keef66 wrote:So is it obsolete as far as modern cars are concerned? And does it still have a place on classic cars?

I only deal with classic car stuff, people still use it and we still sell it. Haven't done a back to back test so don't know how effective it is in reality.
The stuff on the back of modern car pads is probably like what Lockheed used to sell but pre-fitted.

Imposter
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Re: Squealing Ultegra disc brakes

Postby Imposter » Wed Oct 10, 2018 13:56 pm

keef66 wrote:The makers of the alternatives say the copper 'grease' isn't a lubricant, attracts dirt, doesn't handle heat well, and can adversely affect ABS systems.

So is it obsolete as far as modern cars are concerned? And does it still have a place on classic cars?


It isn't a lubricant, and calling it a 'grease' simply perpetuates that misunderstanding, IMO. It is - and has only ever been - an 'anti-seize' compound. In other words, something you put between two surfaces to stop them from binding together through galvanic corrosion. On the other hand, if you want the two surfaces in question to move over each other, then obviously some kind of lubricant (ie an actual grease) is probably more appropriate.

Copper compound still has a place on any item that fits the above description, classic or not.

PhotoNic69
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Re: Squealing Ultegra disc brakes

Postby PhotoNic69 » Wed Oct 10, 2018 15:29 pm

Imposter wrote:
keef66 wrote:The makers of the alternatives say the copper 'grease' isn't a lubricant, attracts dirt, doesn't handle heat well, and can adversely affect ABS systems.

So is it obsolete as far as modern cars are concerned? And does it still have a place on classic cars?


It isn't a lubricant, and calling it a 'grease' simply perpetuates that misunderstanding, IMO. It is - and has only ever been - an 'anti-seize' compound. In other words, something you put between two surfaces to stop them from binding together through galvanic corrosion. On the other hand, if you want the two surfaces in question to move over each other, then obviously some kind of lubricant (ie an actual grease) is probably more appropriate.

Copper compound still has a place on any item that fits the above description, classic or not.


In my opinion I think Copper Slip Anti Seize compound is just as valid today for motor vehicle applications as it ever was. It does what it says on the tin. It stops things seizing. Having worked on many cars most of my life if you ever have to change a set of brake pads that haven't been copper slipped and are seized into the caliper carriers you'll know about it. It is a lubricant too. However, unlike grease it is very stable at high temperatures and wont fling off or get washed away. The movement of brake pads in carriers is very small. Millimeters. Grease is used for stuff that slides lots e.g. bearings.

It has no place on a bicycle. Tried it on my MTB with disks to stop a shriek. Got into a horrible mess and trashed the pads. big mistake. Don't do it.

david7m
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Re: Squealing Ultegra disc brakes

Postby david7m » Wed Oct 10, 2018 15:49 pm

We had new rear pads fitted last week at a nation wide garage and they used copper slip.
Dave

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meanredspider
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Re: Squealing Ultegra disc brakes

Postby meanredspider » Wed Oct 10, 2018 17:11 pm

Imposter wrote:It isn't a lubricant


Well, it is. Even the manufacturers refer to its lubricating qualities. A common definition of a lubricant is something that reduces friction and Copaslip definitely does that and is intended to do that.

Never tried it on bike disc brakes though as I don’t know if the squeal is caused by friction material to disc or pad backing to piston.
ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH

Svetty
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Re: Squealing Ultegra disc brakes

Postby Svetty » Wed Oct 10, 2018 17:40 pm

mlan wrote:Looks like Plodder nailed it. Left some tissue in all day and took it out to find a fairly clear two piston pattern of leakage. So glad to have finally found the problem - it's been driving me nuts for ages! Will look into warranty but if it will take a while I'm just gonna buy new ones.

Thanks for all the help!

Glad you've arrived at a diagnosis. As someone who has yet to buy a disc braked bike, stories like this don't exactly encourage me to migrate from rim brakes but perhaps I am just a luddite?
FFS! Harden up and grow a pair :D

Imposter
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Re: Squealing Ultegra disc brakes

Postby Imposter » Wed Oct 10, 2018 21:35 pm

meanredspider wrote:
Imposter wrote:It isn't a lubricant


Well, it is. Even the manufacturers refer to its lubricating qualities. A common definition of a lubricant is something that reduces friction and Copaslip definitely does that and is intended to do that.


I can't think of a single application for a 'proper' lubricating grease where I would be happy to use copper compound as a substitute, can you?

Lot's of things have 'lubricating' qualities, but that doesn't make them generally useful as lubricants. It's not a 'lubricant' in the sense that you wouldn't want to use it as a layer between bushings, or to pack bearings with. You know, typical 'lubricant' stuff. Incidentally, I just read the copaslip web page, and there does not seem to be any mention of 'lubrication'. Lots of talk about anti-seize though..
Last edited by Imposter on Wed Oct 10, 2018 22:07 pm, edited 1 time in total.

cougie
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Re: Squealing Ultegra disc brakes

Postby cougie » Wed Oct 10, 2018 22:07 pm

Svetty wrote:
mlan wrote:Looks like Plodder nailed it. Left some tissue in all day and took it out to find a fairly clear two piston pattern of leakage. So glad to have finally found the problem - it's been driving me nuts for ages! Will look into warranty but if it will take a while I'm just gonna buy new ones.

Thanks for all the help!

Glad you've arrived at a diagnosis. As someone who has yet to buy a disc braked bike, stories like this don't exactly encourage me to migrate from rim brakes but perhaps I am just a luddite?


You and me both. Maybe it's a learning curve thing but rim brakes have always been so easy to sort in the past. I'm certainly not rushing to replace my bikes.

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meanredspider
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Re: Squealing Ultegra disc brakes

Postby meanredspider » Thu Oct 11, 2018 05:35 am

Imposter wrote:
meanredspider wrote:
Imposter wrote:It isn't a lubricant


Well, it is. Even the manufacturers refer to its lubricating qualities. A common definition of a lubricant is something that reduces friction and Copaslip definitely does that and is intended to do that.


I can't think of a single application for a 'proper' lubricating grease where I would be happy to use copper compound as a substitute, can you?

Lot's of things have 'lubricating' qualities, but that doesn't make them generally useful as lubricants. It's not a 'lubricant' in the sense that you wouldn't want to use it as a layer between bushings, or to pack bearings with. You know, typical 'lubricant' stuff. Incidentally, I just read the copaslip web page, and there does not seem to be any mention of 'lubrication'. Lots of talk about anti-seize though..


I think you have a pretty narrow definition of lubricant/lubrication.

This page https://www.molyslip.co.uk/products/ant ... /copaslip/ refers to easing assembly of tight-fitting components (that’s pretty much the definition of lubrication) and even has a table for correcting torque settings because of the lubricating properties.

I certainly have a tub of Copaslip that I’ve owned for about 20 years and originally bought for the rear of car brake pads. That I’ve had it that long shows it doesn’t have a lot of applications as I’ve pretty much continually restored and maintained elderly Alfa Romeos during that period.
ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH


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