Disc brake squeal

[jaybird]

I've just finished installing a new set of hydraulic brakes and everything is working fine, except for an unbearable squeal under hard braking. Is this a normal part of the break in period for the brakes or should I be looking for something in the setup? Any hints or tips are appreciated. ;)

[yetirider]

I have had this problem in the past too... Not sure what you are using but with Magura's, there is a break in period...

The best way to do this is to get up to about 25 mph or so and break hard!! Do this several times and it should go away!

[jjrsds]

I installed my Hayes brakes and the break in period was around twenty to thirty miles or so. I found an area that had a good long hill and just rode down it a couple of times with the brakes lightly applied.

[martini]

Yep, there's a break-in period for the rotor to go through. It doesn't take very long though. like others have said, 25-30 miles should do it for you. Mine will still squeal when they're cold and wet(in that specific combination). After they warm up a tad, they perform perfectly. I use Avids if it matters. 7" up front 6" rear.

[SickBoy]

The Avids I have on my Salsa have never squealed but there was a definite break in period. The power and modulation on them is a lot nicer now. When I first set them up they felt weaker than the Arch Rival linear pulls I had on my hardtail.

[Trevize1138]

Your brakes don't need to be broken in. That's crazy talk!

Just squirt some WD40 in there and you're good to go!

:crazy:

[jjrsds]

Ok sure WRECK-DEVICES-40. Make sure to change the blinker fluid and check the muffler bearings while your at it.

:shocked:

[Trevize1138]

That's not funny.

Thousands of people die a year because of defective muffler bearings, but the corrupt auto industry won't do anything about it!

[jjrsds]

People are contaminated by di-hydrogen monoxide and are killed by ingesting to much of it as well.

[Tetreves]

Originally posted by Tom S.
For more info on this deadly stuff go here: http://www.dhmo.org/



I think that's the best thing I've seen all day. Thanks! That really made my day.

:laugh:

-ed

[mtnbykr]

try cleaning your rotor/pads w/ rubbing alcohol. don't touch
the rotors and pads w/ your dirty hands. my avids will make
noise when it's humid and cold, or when very dusty or not
at all. :cheesy:

sounds like all discs make some sort of noise.

also move your qr to the side opposite the rotor.

go to the mtbr.com brake forum (http://forums13.consumerreview.com/crforum?14@119.r7CaaCLQBmI.0@.ee7b96e) for more info also.

k

[Trevize1138]

Originally posted by Tom S.
For more info on this deadly stuff go here: http://www.dhmo.org/

Remember if we save just 1 life it will be worth the effort.;)

More evidence why nobody should ever leave their home ... EVAR.

[viv]

are we moving our QRs just to avoid accidentally touching the rotor? Or am I missing some other anomoly?

[mtnbykr]

yup, that's it. keeps you from using the rotor as a grab point to close the qr, which can/will bend the rotor. alos keeps your grubby hands off so the rotor stays cleaner. and if it's hot, you won't get burned....

:crazy2:

k

[funky-funky-chicken]

Originally posted by Trevize1138
Your brakes don't need to be broken in. That's crazy talk!

Just squirt some WD40 in there and you're good to go!

:crazy:

While I will agree with the concept, I prefer Justice Brothers brand product called JB-80. As it says right on the can "twice as good." I'm not advertising for them or anything, but here's proof based on their product specifications:
JB-80®
Part No. JB/80
Helps prevents engine overheating
Multi-use spray product
Protects metal from corrosion
Loosens anything rusted
----> Eliminates squeaks <----!!!
Contains JB Metal Conditioner®

I think it would be a good cure-all for your squeaking brake problem. You will ride much faster not having to work about those brakes making any noise or slowing you down at all.:laugh: :laugh:

[Trevize1138]

Originally posted by funky-funky-chicken
While I will agree with the concept, I prefer Justice Brothers brand product called JB-80.

INFIDEL!

WD40 is the one, true fix-all lubricant spray!

What's next, are you going to abandon duct tape and super glue?

[Kingbozo]

Originally posted by Trevize1138

What's next, are you going to abandon duct tape and super glue?

Hey now-don't forget about bubble gum and bailing wire!

[Trevize1138]

Originally posted by Kingbozo
Hey now-don't forget about bubble gum and bailing wire!

DUH!

How else do you expect to fix a cracked carbon fiber frame?

[socrates]

Originally posted by Trevize1138
DUH!

How else do you expect to fix a cracked carbon fiber frame?

WD40 works too

[Standard]

Back to how to solve disc brake squeels :)

First, make sure nothing is contaminated. Being that they're new, that shouldn't be a problem unless you grabbed the rotor or got some brake fluid on it if you had to bleed them. If they're contaminated, let me know and I'll give you step by step instructions on how to get rid of it.

Next major cause of squeeling is paint on the disc tabs. You can file that off if you're good with a file.

And lastly, most persistant squeeling problems come from mis-aligned tabs on the frame, which often happens during the welding/heat treating process. I'd say over 90% of bikes out there have this problem. If this is the case, you'll have to bring it to a shop with the Gnann-O-Matic tab facing tool (or equivilant) and they can machine the tabs straight. It'll make your brakes feel better, too.

PM/email me if you have any more q's

[fsrslug]

Originally posted by funky-funky-chicken
[B]I prefer Justice Brothers brand product called JB-80. As it says right on the can "twice as good." Back in High school, i built a super mileage car, we did a lot of tests to determine what worked best for our wheel bearings, pretty sure they were just some generic cartridge bearings.
If i remeber right:
1. dry, no grease/lube
2. JB-80
3. WD-40
4. Phil wood tenacious oil
All i am saying is that JB-80 is better than WD-40, I also am not endorsing the company, at least not anymore, I ran out of the free stuff they gave us for our sponsorship package.

Back to the brake squeal. Like others have said, clean the rotors and pads.

A little tip/trick for the pads. Disclaimer: anythign that happens because of this is not my fault.

take the pads out of the caliper
get some dish soap(dawn seems to work pretty good, but anthing should do)
get the pads wet with a little water
lightly rub in the dish soap
rinse off the pads
take a torch and heat up the pads, quite a bit, enough to boil off al the water, try not to burn the pads too much
let the pads cool enough so you can handle them
get some sandpaper(I use skateboard deck tape, whatever grit that is) and sand the pads a bit
blow off the dust ect..I have done this on a few different setups(magura julies, hayes HMX-1, formulas) and have noticed an immediate improvment in stopping power and have not had any noise. Im sure any manufacturer would say this is not good for the pads, but it seems to work for me.

[SilverAthlon]

For cleaning the rotor, i would use Revives "Disc Doctor" a 6oz. aerosol can that is mostly alcohol, but it evaporates quickly and cleanly.


Side note, oils from your hands are easily transferred onto your pads if you handle them. Be very careful not to touch the pad as it can degrade the quality/life of the pad.

Check the spacing of the pads, make sure that they are adjusted to hit at exactly the same time evenly on both sides. Depending on the brake, sometimes there are built in dials that can push the pad close or away from the rotor. Check to see that the rotor is not being pushed one way or another when the lever is clamped.

[manual63]

This is so funny. When I was talking to GeneO at One on One he asked how I liked my brakes. I told him I liked them, but had to grab the rotor to show him a groove that was worn into it because Erik's didn't have it adjusted correctly from the shop. He said, "don't touch that.....". I was kinda like, how am I supposed to know I can't touch the rotors? I guess I better clean them because they do sqeek a little.

By the way, how long do the pads usually last on disc brakes and where is a good place to get new ones?

[mtnbykr]

try the ebc pads that qbp carries.

k