Cure for noisy brakes?

[clouseau]

I know I'm being vain, but I can't stand noisy, squeaky brakes.  
It all started when my OEM pads needed to be replaced. I got some HH Sintered pads from Galfer for better stopping power, since the braking has always been lackluster.  Yes, I'm aware of that compound for our rotors.  But those squeaked rather badly.
My rotors were badly grooved, so I had them turned. (Not a good idea, I realize, but I'm not a track rider.)  They still squealed.  
So now I'm running on Ferodo pads and boy do those squeak as well.
I'm thinking I need to bite the bullet and send my hubs off to Spiegler for new rotors and pads.  Not sure if I have any other options rather than dealing with it.

[Bob_Roller]

There is a product by Permatex, called 'disc bake quiet', it's a blue spray on material, spray it on the metal side of the pad, dries to a blue plastic looking material .

It keeps the pads in contact with the piston, reducing the vibration between them .

Other people on this forum have used cheap 'rattle can' paint and success with this method as well .

I had Spiegler perform the semi-floating rotor conversion on the rotors that came off of my '84 LS, I am quite pleased with the conversion .

The rotors on my '84 LS had been machined down to get rid of the heavy grooving, after I removed the rotor from the hub, I looked the rotors over real closely, and between the two rotors, I found 11 cracks between the drilled holes  .

[Mike V]

Don't forget all new brakes need to be broken in and burnished. This is an often overlooked procedure. Find a safe deserted stretch of roadway free of traffic.  30 mph - brake agressively to a rolling stop not allowing the pads to stay in contact with the rotor. Do this 12-15 times then ride off to cool the brakes - careful not to build up too much heat in the system.  Repeat 3 or 4 times with adequate cooling in-between sessions.

Brake squeal is normally caused by glazing building up by gentle stops and rotor debris. Before sending them off try breaking the glaze from your rotors with fine grit wet-dry paper and cleaning well with acetone. Then break-in with the procedure mentioned above.

Here is a useful link to Mike Morse at Vintage Brake.  I have a very high opinion of Mike and he'll answer the phone if you call in all likelihood.  He can also answer any technical questions regarding sintered pads and the type of rotors you're using.

http://www.vintagebrake.com/tips.htm

[clouseau]

Thanks for the great advice.
I'll be giving the compound between the piston and back of pad for sure.  I do it every time I change the pads in a car so why shouldn't I for the beems?

Mike I don't completely understand when you say "not allowing the pads to stay in contact with the rotor."

[Mike V]

Don't come to a complete stop with the pads in contact with the rotor trapping heat, brake hard but to a rolling pause - releasing the brake, then accelerating to ±30mph again...

[Barry]

My brakes used to squeal. Cleaning the disk and de-glazing the pads would stop it for a while but it always came back. I did try various sorts of gunk on the back of the pads which I think treat the symptoms rather than the cause. Finally they stopped squealing for good after I overhauled the calipers. Maybe it was giving everything a good clean but I put it down to the fact that the  pistons now retract properly so that the pads are not lightly touching the disc all the time which had probably caused glazing especially on my daily commute where I rarely need to use the brakes heavily.

[montmil]

Barry's likely on to something regarding not using the brakes heavily for an extended period.

On occasion, my R65s will squeal a bit. I simply find an open stretch of road and do a couple firm pulls on the brake lever; releasing before coming to a full stop. Squeaks gone.

Something else to consider: If a disc is grooved, it may take some time for the pad's face to wear-match the brake disc's surface. That in itself could account for slight contact and a potential noise.

Monte

[Mike V]

Most brake material is designed to operate at an optimum or certain temperature range, sometimes referred to as a "sweet spot". The break-in and burnish procedure using multiple HARD stops controlling the heat generation is essential for proper operation and recommended by the US Federal Motor Vehicle Safety Standard FMVSS No. 122. This entails 200 brake stops from 30 mph, and is often overlooked or performed incorrectly. Continuous "light" braking will often create glazing and as a result; most often generate squeel. There are molecular gasses formed in-between the friction surface of the rotor and pads. The noise compounds you buy over the counter at your parts store is nothing more than a way of absorbing the high frequecy vibration from your friction pads from the glazing. It may diminish the noise but does nothing to solve the cause. I've used it at times myself.  I'm no expert on the subject but an airhead friend and myself just completed extensive brake shoe testing on /5's and the amount of information that was learned was very valuable. Most valuable was performing the recommendations for break-in using the procedure I described earlier and the resulting enhanced performance of the brake shoes after break-in. None of the brake shoes we tested ever squeeled. Even though we tested shoes and not pads, I feel the results to be similar. I "did" run my /7 with a single 40mm ATE' through the same procedures. Interesting and fun test that taught us an enormous amount of insight. And did wonders for strengthening the right forearm.

[nhmaf]

I'm in the middle of 'bedding in' my new pads on the dual front Brembos at the moment - backroads with little traffic are the key thing.  Some people say to drive in city traffic but I find that usually results in lots of light brake application and infrequently getting up to 30 mph for a brisk stop (without running undesirable risks).

Gotta get teh front pads working nice before I replace the rear shoes - I figure as long as one end of the bike can stop reasonably well I'm OK, but if neither end can....

[MrRiden]

As Bob referred to, this has never failed and is now standard procedure on any pad replacement I do.
http://www.permatex.com/images/DisplayImage.asp?210|/images/ProductPhotos/80077.jpg

http://www.permatex.com/products/Automotive/specialized_maintenance_repair/brake_maintenance_repair/auto_Permatex_Disc_Brake_Quiet.htm

[Bob_Roller]

In the Permatex product description, it mentions an anti-squeal shim in automotive use .

Anyone have an idea what this is ?

[montmil]

My 1986 VW Cabriolet has "anti-rattle" clips -not a shim- on the front caliper assembly. The fingers on the clip contact the pad edges and eliminates a tendency to chatter. I've not yet had a squeal problem in eleven years of ownership.

Monte

[Bob_Roller]

I was just wondering, when I replaced the pads on my Civic, there was a thin sheet metal part between the caliper piston and pad, but no nomenclature listed in the parts catalog for it, as it was considered a part of the pad itself .