Front brakes squealing

[Woooodentop]

At 19000 miles had my front brake discs changed under warranty on my 1200/06 as the techy said they were warped. They did not change my front brake pads which are the original Brembo items as they were less than half worn. Since then they squeal at low speed with a tendency to grab. I reported it to my dealer who apparently test rode it and said he couldn't hear anything, He must have a BMW hearing aid in. I took the pads out to make sure there was grease on the backs and all had gold grease on them so I gave a smear of copper grease to be sure. They still squeal 'badly', could it be the sinters on the old pads not being compatible to the 'uprated' new discs.
Any ideas

 

[The White Rabbit]

Or they didnt put he special whatever washers back on that were used to stop the squeel on the early ones?

 

[Schtum]

I took the pads out to make sure there was grease on the backs and all had gold grease on them so I gave a smear of copper grease to be sure.

Very bad idea..... Have you seen what copper grease or any kind of grease apart from silicone does to brake piston seals. Through time it'll attack the rubber seals which will lead to them swelling up. The pistons will then not retract properly and the brakes will bind. I'd take the pads out and clean all the grease off the back of them. If you must use something, then put on a light smear of pukka brake grease or silicone grease.

 

[Brian ROSEN]

Still squealing !!!

Well, I thought that we had finished with this one long ago. I had enormous problems on my new 2004 model and after months of altering & changing pads and then discs and no improvement a kit of washers was produced by the makers. Essentially just an anti-vibration washer between the steel ones. IMMEDIATE CURE - but that was over three years ago & I thought that was the end of the matter.They even gave me a BMW cap and a fountain pen when I received an apology from BMW France.
(In any case putting partly used pads onto new discs sounds rather penny pinching!)

 

[Brian ROSEN]

I should have said also....

If you have trouble finding these washers (but you shouldn't) let me know and I will try and find out the part numbers.

 

[GSband]

Hi guys,
My brake discs were replaced some 4000 miles ago with the new ones, with the changed washers and mountings (see this link for pictures http://www.ebbo.org/front_brake_fix.php) The brakes don't vibrate or shudder any more and are a definite improvement, esp. when braking for hairpins etc.
Unfortunately wer're back to where we were in 2005 : the brakes squeal at slow speeds. Had my bike in recently, and mechanics didn't notice anything, why am I not surprised, but told me since this only happens when gently braking to a halt, the squealing should disappear when braking hard. They're right, but the squealing is quite annoying, makes you think that the brakes are worn.
If anybody has a solution, I'd be grateful !

 

[Brian ROSEN]

.... gently braking to a halt, the squealing should disappear when braking "hard. They're right, but the squealing is quite annoying, makes you think that the brakes are worn......."
This is EXACTLY the problem I had on my 2004 model when new - and I can assure you that the new washers COMPLETELY eliminated all squealing.

 

[GSband]

Well, yes, ok, that's the problem I had with my '05 model too. BMW then issued a fix for the squealing, but not for the brake discs getting warped, and the uneven braking. BMW THEN provided new discs with different mounts. See link above. But unfortunately these new discs squeal - again.

To be fair, I'd rather have these fineworking discs that squeal, than discs that stutter in silence ...

So, if anyone has a solution to stop the NEW discs from squealing ... THX !

 

[The White Rabbit]

Absolutely 100% what Brian says. Slow speed squeel was an early problem cured by the washer fix. Maybe the techs have forgotten all this

 

[cookie]

Very bad idea..... Have you seen what copper grease or any kind of grease apart from silicone does to brake piston seals. Through time it'll attack the rubber seals which will lead to them swelling up. The pistons will then not retract properly and the brakes will bind. I'd take the pads out and clean all the grease off the back of them. If you must use something, then put on a light smear of pukka brake grease or silicone grease.

i thought that applying copper grease was pretty much standard practice

i'm talking about the slightest trace, not 'kin great dollops mind. not enough to get on the piston seals (it would have to get through the dust seals first anyway).

i've never had any trouble in 30+ years of doing it anyway

 

[Brian ROSEN]

All the remedies

You have to believe that ALL the well tried remedies were tried out on my bike by the dealer in 2005. The main problem was that this noise only appreared on MY bike! Copper grease, chamfered pads, new discs, were all tried - the dealer was more concerned than I was. Then 'they' brought out these washers, They were fitted in about 10 minutes and three squeal free years followed.

 

[GSband]

Brian, I don't disagree with you, in fact, that's what my dealer did with the squealing discs on my 2005 bike too.

The squealing is with the NEW discs with NEW mounts and NEW washers, see below :

I guess there's no fix from BMW for the squealing new discs yet.

 

[Brian ROSEN]

I know how you feel

As you say the brake performance is fine but the noise is irritating. i tried to persuade myself that the police teach the use of the back brake only as you slow down and if I adopted that technique I would have no problem - but I was still irritated; The dealer even took me for a ride on the back (a frightening experience) to demonstrate that squealing could be avoided - but that wasn't the issue!
Accoding to Haynes ".....from 2006rubberised washers were fitted on each side of the disc to minimise brake squeal.If required these can be fitted to ealier machines
I am sure that you have verified that the torque settings for the disc bolts are correct, and the discs are clean (acetone) I will be interested to learn what transpires - if anything!