Results 1 to 3 of 3
  1. #1
    mtbr member
    Reputation:
    Join Date
    Aug 2009
    Posts
    74

    Elixir r does not self adjust

    My rear Avid Elixir R will not fully clamp down on the rotor.

    If I spread the calipers fully open and pull the lever the calipers come in quite far and only retract a hair (so far so good). But I have worn pads and at this point they are barely making contact with the rotor. A second pull should bring the pads in closer Subsequent pulls only bring the calipers a little bit and retract to where it was after the first pull. I've looked at the service manual and can't tell what part is responsible for this self adjustment. I assume it's something in the lever.

    This happened to me last time I spread the calipers and it took about few hours of riding and it fixed it self.

    Please help.

  2. #2
    mtbr member
    Reputation:
    Join Date
    Aug 2009
    Posts
    74
    After posting I continued digging and found this on another thread.
    Quote Originally Posted by RustyIron View Post
    The o-ring seal on the caliper has a square cross section. The piston does not generally slide through the o-ring. Normally, when you pull the lever and the piston moves outward, the o-ring deforms so the cross section is a somewhat distorted parallelogram. When you release pressure, the parallelogram returns to its square state, pulling the piston back with it.

    As wear occurs on the pads, the piston must travel a little further before it is stopped by the disc. The the o-ring distorts to a maximum amount, and the piston is pushed out a little further past the o-ring. When the pressure is released, the o-ring pulls the piston back, but the piston does not slide inward past the o-ring.

    The whole system is dependent upon just right amount of friction and freeness. If one side is a little sticky, it will adversely affect the other side. If the o-rings get hard, or if there is stickiness where they touch the pistons, self-adjustment will be a little off, or they won't pull back properly.
    I'm thinking a caliper's O-ring is failing. Could one failing O-ring affect self adjustment for both pistons? Anything else I should consider?
    Last edited by ScabFace; 10-20-2011 at 03:19 PM.

  3. #3
    Tool
    Reputation: Pedalphile's Avatar
    Join Date
    Aug 2008
    Posts
    1,978
    It's possible that for whatever reason, there is too little fluid in the system. That would prevent the pistons from extending past a certain point if there isn't enough fluid volume to push them further. If you have the means, a proper bleed could potentially alleviate this.

    Too much fluid volume causing dragging is a much more common problem, but too little could cause these symptoms.

    Good luck,
    Pete
    I can barely get my mouth around it.

Similar Threads

  1. Replies: 4
    Last Post: 09-04-2011, 12:07 PM
  2. Replies: 8
    Last Post: 08-27-2011, 01:55 PM
  3. Elixir CR Pad Engagement Adjust
    By billips1002 in forum Brake Time
    Replies: 13
    Last Post: 04-17-2010, 09:44 PM
  4. Elixir CR Pad Engagement Adjust
    By billips1002 in forum Motobecane
    Replies: 0
    Last Post: 04-13-2010, 07:23 PM
  5. Adjust Lever Pull on Elixir R's
    By dhogan5467 in forum Brake Time
    Replies: 0
    Last Post: 09-20-2009, 05:39 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •