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  1. #1
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    Can't keep Juicy 7's from dragging

    I've been using these brakes for almost 700 miles now. They are phenomenal in power and modulation but are a maintenance nightmare. I can true the rotor and line everything up perfectly but it only lasts for 5-10 miles before they start dragging again. The rotor remains true most of the time. The clearance between pad and rotor is only 0.005" though and that seems really small. I know this because the only way I can center the caliper without dragging is to force two 0.005" shims between the pads and rotor and tighten up the caliper bolts little by little until they are tight to prevent twisting the caliper a hair.

    When I went to change the fluid and enhance the power on a friends Juicy 4 brakes, I was putting 0.015"-0.020" shims on either side of the rotor to line it up. Why is my clearance so tight?

  2. #2
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    To much fluid in the system?

  3. #3
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    Quote Originally Posted by Jeff in Bend View Post
    To much fluid in the system?
    This.
    Use a park brake pad spreader or tire lever, or rag-covered flat head screw driver and pry the pads apart while the bleed port screw is removed. A drop or two of fluid should come out and the pistons should retract much farther and easier. Re-install the bleed port fitting. No need to bleed.

  4. #4
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    It's not a fluid thing. I can drain 10 drops of fluid from the system, the lever will hit the bar, and as long as there is enough fluid in the system for the pads to touch the rotor, the pads will readjust themselves at 0.005" off the rotor. I can use a thicker or thinner rotor and will get the same results.

  5. #5
    Tool
    Reputation: Pedalphile's Avatar
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    Your pistons may be sticking, then. You can get more details on the procedure to get them freed up in numerous threads, but you essentially extend them further out, clean them with alcohol, push 'em back in, and repeat until they move freely.

    Here is some more detail

    -Pete
    I can barely get my mouth around it.

  6. #6
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    They aren't sticking but I actually did that this morning hoping to possibly eliminate some problem I can't detect. Without the pads even connected, the pistons move evenly and pull back in to the standard location under normal lever pull. I did push them out as far as I dared, cleaned them, and lubed them up for good measure. No change... I setup the brakes before my ride today and they didn't drag at all. I rode 9 miles and gave the wheel a spin after I got home and it rotated 1-1.5 times before stopping abruptly from brake drag.

  7. #7
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    Well hell, man. I think we've (and you) covered everything. The only thing I can think of now is a skewer/axle/drop-out problem that puts the rotor in a slightly different place each time or after use. Do you have any pad contact adjustability at the levers?

  8. #8
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    The lever allows for modulation adjustment but it doesn't actually move the pads. I snapped the rear axle on my Mavic wheel a few weeks ago and bought a backup wheelset until I could get a replacement. The problem is mainly on the rear wheel and it was a problem on both wheels.

    This bike is a full suspension. The only thing I can think of now is that maybe the rear pivot joints on the frame are shifting or flexing laterally. Probably not enough to make a difference on most brakes but the clearance on these is too tight for that kind of slop in the frame.

  9. #9
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    Quote Originally Posted by ghettocop View Post
    Well hell, man. I think we've (and you) covered everything. The only thing I can think of now is a skewer/axle/drop-out problem that puts the rotor in a slightly different place each time or after use. Do you have any pad contact adjustability at the levers?
    This is easily checked. while bike is upside down, undo the skewer lever to open but don'r remove. Then spin wheel and see if there is any drag.
    2008 Trek Fuel EX 8

  10. #10
    El CicloPath!!!!!!!
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    I've been thinking about all the posts about people experiencing the same thing.

    We spend countless hours aligning, cleaning, truing.....getting the caliper set up right...centered, etc....

    At the beginning of the ride, everything is fine...............we ride for a few miles........

    The brakes start dragging...rubbing..................mine will emit a sound when coasting.....


    I've changed pads....sintered....organincs.......I've changed rotors...tighten the hub bearings.....re---bled......the same result........rub...noise.

    So I got to thinking......these problems occur after I've used the brakes somewhat, or have been on the trail for a ride for a while.
    I'm thinking...................deformation of the swingarm/hub/disc junction.....or.........after some braking.....misalignmentof the caliper.

    I know that we torque the mounting screws done to spec, some of us maybe even more, but I'm thinking that the caliper gets misaligned somehow after we have used the brake for a while. I mean, on descent requiring moderate or hard braking, isn't there a high degree of torque occuring that can twist things out of place?

    I''ve been able to get the brake (rear) to quiet down with organic pads and a new true rotor, but the rub did reappear albeit to a lesser degree,

  11. #11
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    I had the same problem at one time and still have my juicy 7's
    you need to loosen the 2 bolts on the brake caliper
    apply the brake while brake still applied tighten the 2 bolts that will center the caliper and your done.

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