Bicycle Mechanics - Front disc brake drags, causing all kinds of misery

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fit24hrs
06-06-08, 11:18 PM
I searched but couldn't find a clear answer. I have avid juicy ultimates on bike bike and can't seem to get the front brake right. Earlier today, the wheel spun fine. No drag. I don't know what happened but now it looks like the front caliper has closed down on it. I'm still able to spin the wheel but I don't see a gap between the pad and the caliper anymore. No amount of adjusting the "pad contact" on the lever changes this. It just makes the pull shorter or longer. I don't have a manual. Anyone able to point me to a link for a manual or instruction site that shows how you adjust these things? Aren't they supposed to adjust themselves?


Black Bud
06-06-08, 11:26 PM
Are you sure the rotor is still "true"? Rotors do get bent and need to be "trued". There may also be a problem with the trueness of the wheel if the lack of a "gap" between pad and rotor is consistent throughout the rotation of the wheel.

fit24hrs
06-07-08, 06:47 AM
'm fairly sure the rotor is true. I didn't bump it on anything. There's a red dial on the caliper that looks like it needs a special tool to turn. Does that widen the pad contact?


meanwhile
06-07-08, 10:14 AM
I searched but couldn't find a clear answer. I have avid juicy ultimates on bike bike and can't seem to get the front brake right. Earlier today, the wheel spun fine. No drag. I don't know what happened but now it looks like the front caliper has closed down on it. I'm still able to spin the wheel but I don't see a gap between the pad and the caliper anymore. No amount of adjusting the "pad contact" on the lever changes this. It just makes the pull shorter or longer. I don't have a manual. Anyone able to point me to a link for a manual or instruction site that shows how you adjust these things?


Try

www.sram.com/_media/techdocs/06JuicyTechManual.pdf (http://www.sram.com/_media/techdocs/06JuicyTechManual.pd)

- a quick search engine blast with "avid juicy manual" or the equivalent will usually get something like this; hope it helps.


Aren't they supposed to adjust themselves?There are a lot of good things to be said for Avids, but I've never heard that.

kellyjdrummer
06-07-08, 11:51 AM
I'm running Ball Bearing 5's and get the same thing. Don't sweat it, it's harmless.

Black Bud
06-07-08, 01:00 PM
'm fairly sure the rotor is true. I didn't bump it on anything. There's a red dial on the caliper that looks like it needs a special tool to turn. Does that widen the pad contact?

A rotor can go out of true for a lot of reasons, not just a bad bump, and you may not have been aware of what you did to make it go out of true if this turns out to be the cause of your headaches. One of those reasons is an untrue wheel (for whatever reason, including damaged or broken spokes). That, in turn, damages the disc if that wheel is ridden long enough in that condition.

If you and me are thinking the same thing about the "red dial"? Yes, that red dial adjusts the pads. For the ball-bearing (mechanical) models, a special tool is not needed to operate it, just turn the dial. For the hydraulic Avids? I have never looked into whether a special tool is needed or not although I would suspect that the use of the adjuster would be the same at the caliper for hydraulics as well as the mechanicals, although checking the manual would be a good idea before you fool around with the red dial. :)

The link that you got earlier that was supposed to go to the SRAM manual for your brakes is no longer working. The current links page for the tech manual at SRAM (Avid) is :http://sram.com/en/service/avid/view.php?catID=1&subcatID=1 .

The particular manual you need depends on the exact Juicy Ultimate model you have and the year your brakes were manufactured.

fit24hrs
06-07-08, 03:51 PM
Thanks for the responses Black Bud, you've been very helpful. So I figured out that I have several issues. First of all, my LBS sold me a rear adapter instead of a front. Secondly, my rotor is ever so slightly out of true. And third, my caliper is way narrow compared to the rear. I believe I will need a way to turn that "red dial." Any ideas on where to get that tool?
http://i210.photobucket.com/albums/bb13/fit24hrs/avihlsftfr.jpg