[bshelly]

Anyone have any ideas on how I can eliminate the howling, chirping & just plain noisy Saint brakes?

I have tried the following:

Replaced the rotors
Replaced the pads
Clreaned & overhauled the calipers
Swapped out the caliper adapter @ rear (was 7", went down to no adapter 6")

All of the above was done by the Shimano tech guys @ Sea Otter, They also suggested that I reface the calipers to my frame---which I had my LBS perform last week.

----Still howls & chirps like the monkey exhibit @ the zoo when I ride.

My frame is a stock Trek Session 88 with the Saint Brakes F & R.

The Shimano guys hinted that the prob might be due to Trek design of the frame.

I spoke with Trek & they say they are running resin pads on all of their race bikes to eliminate the problem but they are special prototype Shimano pads not available to the public.

Any ideas or suggestions would be greatly appreciated!

 

[jonKranked]

if you've swapped pads and rotors already, try taking a small file to the surface of the brake pads to get a fresh surface (in case it had glazed over).

You can also take a propane torch to the rotor surface (take it off the wheel and hold it with pliers) to burn off any possible contaminants.

Maybe try a different brand of brakepads? As far as I'm aware the only shimano brake pads available to the public are metallic or sintered. Not sure who (if anyone) makes resin pads. I used to run the metallic pads which would sometimes squeal. I'm on sintered now and they are super quiet.

Its not unheard of for a frame to resonate from the brakes. You could always take an old piece of inner tube and wrap it around your chainstays and seatstays to try and dampen the sound. It may not work, but its inexpensive and would be relatively easy to install.


Also, is it just the rear brake doing this? Or is the front brake doing it as well?

 

[bshelly]

Both f & r but predominantly the rear.

 

[Spahman]

have you tried cooking them? I fixed the squeel on my brakes by putting the pads in the oven at 250 degrees for 20 mins

 

[jonKranked]

have you tried cooking them? I fixed the squeel on my brakes by putting the pads in the oven at 250 degrees for 20 mins

Where'd you hear of that method? What does it actually do to the brake compound?

bshelley - I'm assuming you've tried a fresh bleed and re-aligning the calipers on the frame? A lot of times what causes squealing is that the brake pads are contacting the rotor surface completely parallel, instead of at an angle.

Could you share a few more details about what exactly Shimano did to the brakes to improve it?

 

[Spahman]

Where'd you hear of that method? What does it actually do to the brake compound?

bshelley - I'm assuming you've tried a fresh bleed and re-aligning the calipers on the frame? A lot of times what causes squealing is that the brake pads are contacting the rotor surface completely parallel, instead of at an angle.

Could you share a few more details about what exactly Shimano did to the brakes to improve it?

a forum somewhere... it works REALLY good at cleaning off brake fluid if you get some on the pads

 

[sanjuro]

Next time you see a Trek service tent, ask for those special pads. Be real nice about it, and they should give it up.

 

[jonKranked]

a forum somewhere... it works REALLY good at cleaning off brake fluid if you get some on the pads

Or you could just not get fluid on your brake pads in the first place




After being a mechanic for so long, one thing you learn: always take the pads out when bleeding.

 

[w00dy]

If they're howling, contamination probably isn't the issue. Sandwich's old hope brakes did it, and the only way he could fix it was to swap to organic pads which have different grip properties, but also wear faster. I think what worked best was a combo of 1 organic and 1 metallic per caliper.

My theory, your brakes howl at a frequency which the frame likes and resonates well. The one time I had a problem like this I solved it by zip-tying a bmx grip flange to the base of the rotor. The soft rubber does wonders for absorbing vibration. You also might be able to kill the noise with a significantly different rotor design.

 

[boxxerace]

If they're howling, contamination probably isn't the issue. Sandwich's old hope brakes did it, and the only way he could fix it was to swap to organic pads which have different grip properties, but also wear faster. I think what worked best was a combo of 1 organic and 1 metallic per caliper.

My theory, your brakes howl at a frequency which the frame likes and resonates well. The one time I had a problem like this I solved it by zip-tying a bmx grip flange to the base of the rotor. The soft rubber does wonders for absorbing vibration. You also might be able to kill the noise with a significantly different rotor design.

Along with this, I believe it often is the slight vibration of the rotor caused by a mis-shimmed / welded brake caliper (the mount in the latter case). V-brakes and automobile brakes howl for the same reason.

Finding out why this occurs can be tough. It could be that you are missing your pad retainer pins, or that they are worn. I suspect some act as vibration dampers, as they do in car brakes. Perhaps look at how the piston is pressing on the pads, is the piston slightly out of alignment? Try centering the rotor in your caliper (no duh, I know) and depress your pistons in all the way. Then, pump them back into place and give it a try.

 

[Jim Mac]

It might not be related, but some of the Klein 'Trek era' FS frames had this howling issue as well - from the few I have seen, it was essentially resonated/exacerbated by the frame.

 

[Sghost]

Be happy they are slightly under snuff. If they were at full power, your frame might buckle before you crash it.

 

[jinshiyang]

You could always take an old piece of inner tube and wrap it around your chainstays and seatstays to try and dampen the sound. thread insert helicoil

 

[zebrahum]

There is a resin pad available from any bike shop, they have a silver backing plate instead of the goldish one on the sintered pads.

I also know there is a motorcycle product that you brush on a spot of the rotor. I've used it a couple times with some success. I'm sorry, but I can't remember what it's called.

 

[cowman]

I'm also having this issue with a Session and a Saint caliper. As a former mechanic, I've tried all obvious things. I'm curious if bshelly was ever able to find a solution?

Thanks!

 

[Mo(n)arch]

I ride with organic pads only. It solved the howling.

 

[Mr Jones]

On my M9, I solved the noise on my Saint M810's mated to new (non ice tech) XT rotors by swaping out to the old style XT rotors. Figured the cutouts on outer and inner edges of the the braking surface were the ones causing the garble when the pads hit them. Old style rotors with M810's were instantly quiet.

Old

New

 

[Konabumm]

I also have a Session 88 but not saint brakes. However, in the past I've had problems with noise and every time I've had this problem the following worked for me.

1. Clean the rotors with alcohol (I've even put my rotors in a pan covered them with alcohol and set them on fire.) it's a fast burn and will not warp your rotor.

2. Use a dremel tool with a wire tip

and run it over your brake pads.

This has always worked for me.

Good Luck