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[Closed] Diagnose my Brake Squeal!

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Front brake squealing like a stuck pig. Its continual. Its driving me mad.
Its on Deore M575 calipers, on On One 29er Carbon forks.
I've bled them. I've replaced the pads. I've greased behind the pads. All to no avail.

Is it time for BB7s?

Cheers for your useful/amusing comments.


 
Posted : 30/06/2011 3:35 pm
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Swap the front rotor and pads with the rear ones. See if the noise moves or not to eliminate that. Assume you've checked all bolts are tight and alignment is okay etc?


 
Posted : 30/06/2011 3:41 pm
 TimP
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Sorry can't help without hearing it. Can you upload an example squeal

like this

or more like this


 
Posted : 30/06/2011 3:51 pm
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Pads may have a spot of oil contaminating them, it doesn't take much.


 
Posted : 30/06/2011 3:59 pm
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Much as I like my BB7s, i'm still trying to find a set of pads that don't squeel in the wet, so they're maybe not a solution.

However, we had a big batch of OEM Deore Brakes fitted to Marin bikes which were pre-contaminated due to leaky callipers. You could check by removing the pads, placing an 8mm allen key between the pistons and pulling the lever till the pistons clamp the allen key, if there's a leak you'll see it bubbling out round the piston.

Also, make sure the rotor is 'swaying' in the correct direction, having the arms rotating backwards can cause an unbelievable amount of noise.


 
Posted : 30/06/2011 4:08 pm
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[url= http://www.muc-off.com/shop/product.php?id=7 ]Muck Off[/url]


 
Posted : 30/06/2011 4:12 pm
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For me I found out it was oil from a leak on my forks running down the leg when I stored the bike :(. Serviced the forks and changed the pads (again).

I also noticed the rotor was scored which probably didn't help. IS your rotor tight and unmarked?


 
Posted : 30/06/2011 4:17 pm
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Calliper and disc aligned and faced correctly?


 
Posted : 30/06/2011 4:36 pm
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Pistons leaking

Mine did.

Didn't know until I got to a junction though and didn't stop quite ask quickly as I would have liked.


 
Posted : 30/06/2011 7:23 pm
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Could be dozens of things. Take it to a shop or let somebody who knows what they're doing get their hands on it.


 
Posted : 30/06/2011 7:29 pm