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  1. #1
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    Leaking XT M785 Brake?

    I've had my XT brakes for a little over a year now and they have been awesome... But then I took my bike out for a ride a month ago. My front brake had pretty much zero stopping power and the caliper was just howling, so I knew my pads were contaminated. The braking power eventually returned to normal over the course of the ride though, so I figured that whatever was on the pads/rotors had disappeared. The problem is back again now. I can't see any oil residue on the calipers and I don't seem to have any air in the system indicating a leak, even when I pull the lever repeatedly with the bike upside down. So I'm wondering if I have a leaky brake or did something external contaminate it? I did lube the pistons maybe a week before that ride with the same brake fluid used in the system. I cleaned up the caliper thoroughly with isopropyl alcohol, but could this cause it in anyway? My rear brake is perfect.

    Thanks!

  2. #2
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    Pull the pads, pour some boiling water over them, let them dry then give them a good sanding to remove the top coat and you should be GTG. My front started keeping noise about a month back and that's what I did and it solved the problem, guessing that the pads somehow got contaminated and just needed a good cleaning.
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  3. #3
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    I decided to clean up the brake thoroughly with iso. alcohol and I coated the caliper with baby powder and squeezed the lever with a clamp. I'm going to leave it like that for a day and if any oil leaks out then I should see it in the powder. If it's the caliper then I'll try to do a warranty fix, if not then I'll try your idea Lynx. The finned pads are quite expensive!

  4. #4
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    IIRC there was a batch of these brakes about a year ago that had bad crimps where the hose entered the banjo fitting - and the oil can make its way down to the pads. Worth checking there too...

  5. #5
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    Yeah, I know about the crimp on the hose, so I made sure to check that too : )

    I found that my caliper and hose were not leaking at all so I just replaced the pads. I found some none finned ones locally and bought a few of those. My front brake is powerful again!

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