Author Topic: Disk brake squeal  (Read 1515 times)

Svend

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Re: Disk brake squeal
« Reply #30 on: October 26, 2012, 08:21:38 am »
Jim, way back in this thread, before you discovered the missing pad, Epic and I talked about centering the brake calipers and straightening rotors.  I just came across this video that shows a few easy methods to do both tasks:

http://www.mountainflyermagazine.com/view.php/macky-franklin-blog-centering-disc-brakes.html

Something to file away in your bookmarks for future reference.

FWIW, the Avid brakes on my wife's bike seem to be susceptible to getting out of center, as I have to do this frequently.  I think I'll bump up the torque setting a bit to make the calipers tighter to see if that will fix it.  Very annoying to have to do this once a month.

« Last Edit: October 26, 2012, 08:24:31 am by Svend »

jim-ratliff

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Re: Disk brake squeal
« Reply #31 on: October 26, 2012, 09:15:21 am »



Svend:
thanks. One of the other tips I got from the local bike shop is to just insert a business card between the rotor and the brake pad on the side that's rubbing (without loosening the caliper) and clamp the brakes as a way of getting that piston to retract a bit more.  I've done that a time or two with success -- however, it didn't help much when Lynn's pads were completely gone.
« Last Edit: October 26, 2012, 09:18:43 am by jim-ratliff »
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Svend

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Re: Disk brake squeal
« Reply #32 on: October 26, 2012, 09:34:31 am »
Good tip.  But how do you slide the card in if the pad is tight against the rotor? Bend the rotor slightly by hand until it slips in?

One thing is for sure, on all our next bikes, we will have QR15 thru axles.  I think half of these problems are caused by things getting misaligned by the 9mm QR off/on/off/on thing.  There will be far less fiddling around....


jim-ratliff

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Re: Disk brake squeal
« Reply #33 on: October 26, 2012, 09:57:10 am »
Good tip.  But how do you slide the card in if the pad is tight against the rotor? Bend the rotor slightly by hand until it slips in?

Hmmm. Good question.  I've always been able to hold the card (or a similar piece of heavy paper) against the rotor and rotate the rotor and get the card to go under the pad with the rotor. So yes, that may be displacing the rotor to the side a little bit as it rotates?
"If you're gonna play the game boy, ya gotta learn to play it right."

Svend

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Re: Disk brake squeal
« Reply #34 on: October 26, 2012, 10:07:22 am »
Probably the rotor is not perfectly true (most aren't), so you're slipping it in at a bent spot.  Regardless, it's a nice quick fix that doesn't need any tools.  Good for trailside.  Thanks -- I'll definitely use that one.

However, eventually the piston will end up back where it was, and you will have to use a proper alignment method -- loosen caliper bolts, etc....

Did you notice that in the video, he was working on Shimano brakes? So those methods will work for yours just fine.

« Last Edit: October 26, 2012, 10:15:23 am by Svend »

jim-ratliff

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Re: Disk brake squeal
« Reply #35 on: October 26, 2012, 11:11:54 am »
Yep, the rotors looked very familiar --  same Shimano XT as mine. Method 1 was the same as you and Epic described. Method 2 was an interesting adaptationof that.
"If you're gonna play the game boy, ya gotta learn to play it right."