Squealing brakes

[retiredgentleman]

My front and rear disc brakes were quiet the first few years. The rear brake started squealing first last year, and now the front is squealing as well.

The caliper pistons move freely and the calipers sliding surfaces are fine as well. I tried using the "Disc Brake Quiet" product applied to the back of the pads. It seemed to work for a short while, but squealing returned. I also tried chamfering the edges of the pads, but again no joy.

The pads I have are the semi-metallic ones sold by Mikesxs. I have also tried roughing the disc rotors using 40 grit sandpaper. The stopping power is quite good, but the squealing is annoying.

Perhaps the semi-metallic pads are the problem, and I could go to the organic pads such as the Ferodo Platinum. There is the option to change over to something like Brembo calipers.

I know everyone has a theory as to why brakes squeal. I'd like to hear from someone who has had squealing brakes and actually found a lasting solution.

 

[DogBunny]

As you said, the solution is to apply anti-squeal or Brake Grease to the back of the pads. The squealing has nothing to do with the pad or rotor surface. And yes, the grease does not last forever, and the squealing might return.
While researching Threebond, I read that one of its stated uses is as an anti-squeal dressing for the back of brakes. I believe it is touted as lasting longer than the greases.
Although they don't show up in any of the fiches, XS650 brakes were equipped with the anti-squeal shims shown in my picture. I have run into a few of these. I do not now if they came on all years. They do work, but I believe that they are commonly thrown away during pad replacement time by owners who don't know how to spread their pads and are therefore looking for more rotor clearance.
Anti-squeal shims do show up on the older, round-pad, dual-piston XS650 brake fiches.

 

[retiredgentleman]

DogBunny;

Thanks for the reminder to look at the parts fiche. I just had a look over at www.biker.net. The 1978SE parts diagram for the front and rear brakes do indeed show a shim on the piston side pad only., i.e. 1 shim per caliper. The diagram shim looks similar to your right side picture. part # 1J3-25827-00-00

I feel a little dumb, having had the bike for 5 seasons now, and not realizing there should be a shim in each caliper

Interesting that the pad compressed by the caliper body does not show a shim in the fiche.

 

[DogBunny]

Well, I learned something too. That shim is different from the ones I've run in to, but it is still available:
https://shop.zanottimotor.com/part/1j3-25827-00-00

 

[xjwmx]

Mine has squealed both with and w/o the shims. Right now it squeals like a train trying to miss a school bus. But not every time. I got some kind of permatex brake quiet glue I'm going to try, not grease. The sound originates between the pad and the caliper when vibration sets up. My rear drum squealed after the last time I had it apart. I sanded it and the shoes with 50 grade emery paper and it stopped. It was a really embarrassing squeal, like a silly honk.

 

[retiredgentleman]

I did some more searching. The fiche for 1979 and 1980 does not show any shims for the pads. However, the fiche for 1981 and 1983 does show shims.

piston side.........3H5-25827-00-00
caliper side.........3H5-25828-10-00

I'll talk to my local Yami dealer to see if they can order them for me.

 

[DogBunny]

Yeah, that's the stuff... What I researched was not Threebond as I wrote above, but Hylomar, which is second-party marketed by Permatex in the U.S. Hylomar is a non-hardening, non-drying gasket sealant, that also works as a disc brake squeal preventative.

I had an old Sportster a couple of years ago that if I held the lever pressure just right would make a loud, sustained squeal. I would make it do that squeal on purpose whenever I came to a red light, just so that the cages would know I was there. When I got ready to sell that bike I eliminated the squeal by putting Brake Grease on the back of the pads so as not to scare off any potential buyers.

 

[ReycleBill]

Yeah, that's the stuff... What I researched was not Threebond as I wrote above, but Hylomar, which is second-party marketed by Permatex in the U.S. Hylomar is a non-hardening, non-drying gasket sealant, that also works as a disc brake squeal preventative.

I had an old Sportster a couple of years ago that if I held the lever pressure just right would make a loud, sustained squeal. I would make it do that squeal on purpose whenever I came to a red light, just so that the cages would know I was there. When I got ready to sell that bike I eliminated the squeal by putting Brake Grease on the back of the pads so as not to scare off any potential buyers.

Loud brakes save lives! Who would'a thunk it?

 

[retiredgentleman]

Here's a pic of the stuff I tried to stop the squeal. It looks pretty and stays rubbery, but it just does not work.

Hylomar is an excellent sealant................can be used similar to threebond 1104 i.e. joining metal to metal surfaces. I used it back in the 1980's for engine work. Yes, I suppose it could be used for brakes. In those days, Hylomar was made by Rolls-Royce in England.

 

[itsagivens]

I purchased a new front caliper from 650 central and the upgrade pads for my XS2, it came with shims, do I need to install the shims?They are a pain to install!!!

 

[xjwmx]

Just pulling my caliper off and putting it back on fixed my bad squeal. I had it off to work on the forks. Been over a month and the squeal hasn't returned.

 

[CDNTX650]

my 74 squeals like a mofo too.

 

[mouser]

Permatex "Anti Seize" on the back of the pads fixed my squeal. Not a peep out of them all summer.

 

[1974jh5]

Both the front and rear on my '80 squeal but only after they get warmed up.

 

[weekendrider]

Would there be a difference if the sqealing was happening when brakes were applied?
Fixed by adding something between the pad and shim.
And the squeal from the caliper not "floating". Fixed by replacing the old hard rubber bushing?

 

[retiredgentleman]

Thanks guys for all the input on brake squeal.

I've decided to go a different route. I've bought some used Brembo calipers; goldline 4 piston for the front and goldline 2 piston for the rear. This should give me improved braking and maybe no squealing???

 

[KentMoney]

nice, how you going to mount them?

 

[retiredgentleman]

The Pandemonium shop (HappyDan)has an adapter kit for the front caliper. For the rear caliper, I will likely make up my own adapter plate/link.

 

[KentMoney]

get 'er done!

 

[blackbetty]

RM, I fitted the 4 pot Goldline on my 75. Even with 34mm forks, my bike's stopping power is one of it's best qualities. I fitted new EBC pads and the operation is silent.