Canyon wedge expander stuck

maton Posts: 13
edited June 2019 in Workshop
Hi all,

I am having problems with the wedge expander on my Canyon. For some reason, the bolt and the wedge are threaded and I am not able to firmly install the stem cap anymore.

Canyon has already sent me the spare parts, but I am unable to remove the old wedge expander. It is stuck and I have no idea how to take it out without causing damages to my carbon fork. Any suggestions?

I attach a few pictures hoping they will help you understand the problem.

Thank you.




  • sungod
    sungod Posts: 16,535
    looks like it simply takes a hex key to tighten/loosen it - the 4Nm engraved is presumably the torque to use when tightening

    give the hex key a few turns to loosen it, if it doesn't drop out make a hook out of a piece of stiff wire and pull it out
    my bike - faster than god's and twice as shiny
  • drexel1975
    drexel1975 Posts: 70
    Funnily enough I had the exact same thing yesterday. I had a crash on my Canyon and the frameset was written off. I was removing the handlebars and thought I might as well take out the expander as well. Stuck solid. Because my forks were already written off I cut the steerer and gave the expansion plug a chap out from the bottom, obviously you can't do this, but it took a fair chap to knock it loose. It almost looked as if it had cut into the carbon. Definitely not the best expander plug I've seen. Good luck getting it out anyway.
  • maton
    maton Posts: 13
    Thank you both for your replies.

    I have tried to loose the wedge with the hex key but nothing. The wedge doesn't want to move. I am tempted to loose it completely to (hopefully) create a bigger hole where to insert something as leverage to take it out, but I don't want to make the situation worse.

    I really don't know what else to try :(

    @Drexel: sorry to hear about your crash.I hope you are fine!
  • sungod
    sungod Posts: 16,535
    if it won't move, leave it there

    just push in the replacement one and tighten

    the top cap bolt should only need c. 2Nm at most, it's main purpose is to preload the bearings before tightening the stem, if the thread in the old expander was stripped the torque must have been way higher
    my bike - faster than god's and twice as shiny
  • maton
    maton Posts: 13
    Thank you, Sungod.

    I didn't think about this solution. I should start thinking more out of the box :P

    I need to check whether the new wedge would go down enough to leave room for the spacer provided with the bolt.
  • sungod
    sungod Posts: 16,535
    as you have a new one, examine it to see how it works, that can indicate how best to attack the stuck one

    from the images, looks like the two metal ends are closed together by the hex key, forcing the rubber bit outwards to grip the steerer, once it's in the rubber probably is gripping the upper metal end and maintaining the compression

    if you loosen off the hex key as far as it'll go, then put a screwdriver through the hole and wiggle it, that may allow you to move it enough to release the compression

    or, if you are comfortable doing it, another option is to drill out the old one, depends on the construction how much material you'd need to remove to weaken it enough

    or you may be able to simply screw a long bolt with slightly larger thread (self tapping, or tap a new thread) into it, that may give you purchase to extract it

    important thing is to avoid any damage to the steerer
    my bike - faster than god's and twice as shiny
  • jermas
    jermas Posts: 484
    Install the stem. Put a top cap or large washer(+bolt) on top of the stem and thread the bolt onto the expander. Keep turning bolt. This should pull it up to the top of the steerer.
  • jeddy11
    jeddy11 Posts: 16
    A bit of soapy water or oil may facilitate movement this would have to be cleaned up afterwards .

    The above suggestion to make a puller is a good one.
  • I just got a new Ultimate CF SLX 8.0 and this happened to me while setting it up. It seemed like Canyon shipped the bike with the expander somewhat loose so when I was installing the top cap, the expander just slid down the fork.

    Extremely frustrating.

    I took it to my local bike mechanic as I couldn't get it out. He used a long allen key (6mm I believe) to slowly slide it up and get it out. He was surprised Canyon has not updated this piece yet. As other expanders come with a ring at the top so they don't slide down further than they need to.

    He pulled the expander plug open and greased all of the internal surfaces, while adding assembly paste to the outside. This helped and when we put the expander back into the fork, it did not slide as much. Turn the hex key slightly before sliding it to make sure it expands enough and put it in the height that you need. After you are sure that it no longer slides, you can reinstall the top cap and ensure not to go beyond 5Nm.

    FYI - The expander has a super small hole on one of the sides, so if you have an extremely thin allen key you can slide it into the hole, to ensure it does not move while turning the hex key.

  • Darius_Jedburgh
    Darius_Jedburgh Posts: 675
    edited May 2020
    Same happened to me. Expander fell down to the bottom of the tube. Wouldn't come out. I turned the bike upside down and no luck. Tried everything, finally resorting to some araldite on the end of a rod. Expander is stuck so fast that the araldite broke.

    I took the practical option and left it there and replaced it with a different type - meant I could go all blingy and have a green stem cap!!!
  • Sounds like you got the problem sorted. If you need spare parts you can just drop Canyon an email or use the live chat. They've sent me out spares FOC before. You can always replace their expander with a PRO one that won't slip down.