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  1. #1
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    Rebuilt Juicy 5 Not Retracting

    I have a pair of Juicy 5's that I picked up a rebuild kit for and rebuilt them. I've replaced all seals in the caliper and bled the brakes exactly as the directions specify. Now it seem that whenever I first press the brake the calipers never retract back. I can just press them a few times and the pistons will eventually exit the caliper. I've rebuild/bled them over five times now. There's no air in the system as far as I can tell since there was none in the syringe. Any ideas what I could be doing wrong? I tried getting some of the brake fluid out by pressing the pads back in on one of the rebuilds and that sort of worked but the brake had barely any power in it.

    Thanks for any help.

  2. #2
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    The square seals are twisted? The pistons aren't sitting square in the bores? The square seals are defective? Did you lube the pistons/square seal when you pressed the piston back in?

    Is the lever returning after being released?

  3. #3
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    Quote Originally Posted by XSL_WiLL
    The square seals are twisted? The pistons aren't sitting square in the bores? The square seals are defective? Did you lube the pistons/square seal when you pressed the piston back in?

    Is the lever returning after being released?

    Thank you! This is just what I needed to go on. I think I overlooked some of these things.

  4. #4
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    Well gave it a few more shots and screwed up a Juicy 7 in the process. Have a new Juicy 7 that wasn't reaching the rear wheel. Took the 5's cable and put it on the 7 to extend it (didn't really want to do it but figured screw it). Bled the system and exactly the same thing happens. After bleeding if I pump the brake the calipers just come fully out on both sides. I know this brake should work as it's brand new or at least it was.

    Popped the 7 pistons out with an air compressor, lubed the rings with the brake fluid, put them square back in, looked even on both sides. Put it back together bled the system, still pop out. The lever does return to it's position after being pressed.

    The closes I've got so far is to bleed the system, pump the brakes a few times, open the lever valve and press the brake pistions back in. The brakes start to work then but they feel sloppy when I put the wheel on; they do retract though.

    So far this has become an expensive ordeal, well $150 in but I really want to know what I'm messing up on. The 7's brand new the 5 has the rebuild parts on it but both do the exact same thing after I bleed them.

  5. #5
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    Rebuild the brake (juicy 7) at least five more times, still wont retract. Tried pushing the pads back by using a worn pad and a butter knife. Pushed each side back, and pumped the brake a few times to get them out again. Did this over ten times, still didn't come loose. Getting pretty disappointed, I've been at it for the last three days.

    Any recommendations on how to put the pistons in straight? I lubed them with the DOT fluid and used an old brake pad to push the piston into the brake. There's nothing in the technical manual on how exactly to push them in.

    Thanks for any help or just if you've read this far.

  6. #6
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    Could you describe from start to finish the process by which you're bleeding the brakes? Don't leave anything out...

    (Also, try using a plastice tyre lever to push pistons back, always keeping pressure at the dead-center of the piston to avoid it twisting in the piston bore.)
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  7. #7
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    Quote Originally Posted by norcom
    Put it back together bled the system, still pop out. The lever does return to it's position after being pressed.

    The closes I've got so far is to bleed the system, pump the brakes a few times, open the lever valve and press the brake pistions back in. The brakes start to work then but they feel sloppy when I put the wheel on; they do retract though.

    With out pads in place, you can always pump the pistons all the way out with several strokes of the lever.

    If you have the pads and wheel (disk) in place and "they feel sloppy" you need to bleed them correctly and get the rest of the air out.

    edit: or take it to a lbs and let them do it so you don't waste any more time or $$$

  8. #8
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    If the system is overfilled, then the pistons won't want to retract. Try pushing the pistons in with the lever bleed port open.

    Is the hose obstructed at all? Kinks? The barb is inserted properly?

  9. #9
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    Quote Originally Posted by gmcttr
    With out pads in place, you can always pump the pistons all the way out with several strokes of the lever.
    If you have the pads and wheel (disk) in place and "they feel sloppy" you need to bleed them correctly and get the rest of the air out.
    edit: or take it to a lbs and let them do it so you don't waste any more time or $$$
    Well that could be it, all the time that they pop out is because either the pads or the disk aren't in place and I pump the brake a few times. I was under the impression they should retract no matter what.


    Quote Originally Posted by SteveUk
    Could you describe from start to finish the process by which you're bleeding the brakes? Don't leave anything out...
    I've followed the bleed kit instructions and the SRAM instructions online to the tee every time, step by step. I've had the laptop next to me playing the SRAM video http://www.youtube.com/watch?v=6mg6NbIjmOM. I've tried my own variations of not pulling ont he syringe as hard as I thought I may have. I had every bubble out of the system and thought maybe I was pulling air past the seals, so I pulled light on some occasions hoping to leave some air in and maybe it would retract. On some occasions I didn't press down onto the syringe to not overfill the brake system. Basically trying not to overfill.


    Quote Originally Posted by XSL_WiLL
    If the system is overfilled, then the pistons won't want to retract. Try pushing the pistons in with the lever bleed port open.
    How can I tell if the system's overfilled? I have tried opening the lever port, placing an old pad on one side of the brake and pushing the piston back with a butter knife . Then doing the same thing on the other side of the caliper. It did get some of the fluid out but I was still able to push the pistons out.



    I'm going to try this again and put the pads and the wheel back in and see how that works out before trying to pump the brake. I thought that the pistons just have to retract fully back into the caliper with or without the pads or the wheel. If that's not the case than I'm just an idiot who rebuild and bled the brakes at least 20 times now for no reason.

    Thank you guys.

  10. #10
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    A full lever stroke moves the pistons out farther than they retract so you can pump them right out of the calipers.

    This is also the reason with pads in, but no disk in place, if you hit the lever a few times the pads will be tight together and you have to pry them apart to get the wheel back on.

    That is also why Avid makes these spacers.

    At least you have something to work with now.
    Attached Images Attached Images

  11. #11
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    "I've followed the bleed kit instructions and the SRAM instructions online to the tee every time, step by step."

    Blimey, that's a bit convoluted!!

    Assuming that all your seals, including the lever piston seals, are working as they should, I'd suggest doing one more bleed, but this time remove the pads - when you're happy that the line is free of air, use a tyre lever to push both pistons back so that they are flush with the caliper interior. Leaving the lever bleed port open as Will suggested will allow any excess fluid to be pushed from the system at this point. With the pistons properly retracted, close the port, refit the pads and wheel, confirm that the caliper is centered over the rotor, then pull the lever a few times until the pistons have been brought out to their working position. If the pistons actually aren't retracting, you'll get to the point where the lever can't actually be pulled, because the pads will be permanently pressed against the rotor.

    With new seals, it's possible that one piston moves faster than the other, or even that only one is actually moving. Eyeball the pads and rotor as you pull the lever - if the rotor is flexing laterally as you pull the lever, then the pistons require equalising, something that you can do by pulling the rotor against the working piston/pad while you or somebody else pulls the lever to force the other piston into action.
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  12. #12
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    The pistons do not fully retract when you release the lever. It should retract enough that it doesn't rub (perhaps a mm per side).

  13. #13
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    Took the 5's cable and put it on the 7 to extend it
    Maybe that's the problem

  14. #14
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    This might be a stupid question, but have you tried to just put pads on, install the wheels and ride? The retraction is very slight and (no offense) your description of what is happening is a little vague. This is why you shouldn't pull the lever with no rotor in place, the pistons will work their way out-they will never retract themselves (completely) back in unless you force them in. (this is how hydraulic brakes self-adjust as the pads wear)

    OR,

    Are you saying you have tried mounting wheels with rotors and the pads do not retract at all and continue to drag harder and harder with each use of the brakes?

    I don't mean to sound rude, but it sounds like you want a partially assembled brake system to work as if it is assembled.
    You better just go ahead and drop that seatpost down to the reflector... the trail gets pretty rough down there.

  15. #15
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    Quote Originally Posted by Uncle Six Pack
    This might be a stupid question, but have you tried to just put pads on, install the wheels and ride....... This is why you shouldn't pull the lever with no rotor in place, the pistons will work their way out-they will never retract themselves (completely) back in unless you force them in.
    I haven't had a chance to mess with the bike today, but I believe you're right. I did try to ride once; about 10 or so rebuilds/bleds back and it worked fine. But I thought that the pistons were supposed to RETURN ALL THE WAY BACK into the caliper and I wanted them to do it without being on the wheel. So I set out on a quest to get them to do that.

    I'm pretty confident now that the only thing I was doing wrong was not installing the brake pads, the wheel and just trying to ride. I didn't realise they just need to go back a millimeter, I thought they're supposed to go all the way back.

  16. #16
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    Quote Originally Posted by Jerk_Chicken
    Maybe that's the problem
    Thought about that too, rebuilt the 5's with the 7's cable and both pistons came out when I pumped on them. But as I've said above, it was because they weren't mounted on the wheel with brake pads. I thought the pistons are supposed to retract all the way back into the caliper fully.

  17. #17
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    "Thought about that too, rebuilt the 5's with the 7's cable and both pistons came out when I pumped on them."

    Neither brake uses cables, is what JC was alluding to. Hydraulic brakes use hose.
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  18. #18
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    Quote Originally Posted by norcom
    I'm pretty confident now that the only thing I was doing wrong was not installing the brake pads, the wheel and just trying to ride.
    OK, yeah.

    Put that thing together and ride it. As long as you get a firm lever feel and the brakes retract enough to keep from dragging, you are good to go. Only bleed again if the lever feel is kinda "mushy".
    You better just go ahead and drop that seatpost down to the reflector... the trail gets pretty rough down there.

  19. #19
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    Well.............................

    Bled the brake, probably took me < 5min ... + cleanup.. put the wheel on and it works just fine. They retract just enough to let the rotor spin freely. They're not mushy and feel very firm and perfect. They work great too!

    I can't believe the manual does not state that the brakes need resistance to be tested. They need to include a warning that pumping your brake without pads/rotor will ALWAYS result in piston extrusion and that the piston does not return all the way. At least for people like me. Oh well.. live and learn.

    Thanks for all your help! My next set of brakes will definitely be from Avid I think. LOL I can rebuild it now. LOL Whoooo!

  20. #20
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    Congrats...glad to see you are back in business. Go ride.

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