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  1. #1
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    Stuck Dropper Post

    Recently when switching frames I could not remove my KS Integra dropper post. I tried every technique I could find (letting anti-seize sit for days, heat gun, dry ice, blowtorch, etc. you get the idea) with no luck. I had my lbs try to remove it and they couldnít either.

    Iím at the point where Iím certain it has to be cut, a hole drilled through it, and removed that way. However I know my dropper post has an internal air chamber. Anyone have any experience removing a dropper post this way? I want to avoid puncturing the air chamber during removal. Itís an aluminum frame and dropper.

  2. #2
    Mudhorse
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    You've grown aluminium oxide crystals that are now exerting enormous pressure between the seatpost and seat tube, and the two parts are now effectively chemically welded. Rust releasing compounds ain't gonna shift it, and the force required to break the oxide bond is undoubtedly greater than the force required to destroy the frame.

    I had the same thing happen on an old steel Scott frame that was given to me. It was no longer any good as a frame so I wanted to remove the seatpost and turn it into a wheel truing stand. I had the seatpost clamped into a 1-ton bench vice while I wrenched the frame: nothing doing. Similarly, swinging a 20 lb sledgehammer didn't budge it in the slightest. Eventually I admitted defeat and just sawed the seatpost off.

    Anyhoo, back to frames you don't want to destroy: I think in this instance you're going to have to remove the oxide by chemical means. I've heard some people have had success with citric acid (or even lemon juice), but it can take a few days of dripping it down there before it works. Alternatively seek out a specialist who can deal with nasty chemicals (e.g. chromic acid) that are too dangerous for home use. An anodizing plant would be a good place to start, they've got all sorts of techniques for stripping aluminium oxide. Bear in mind there's a danger here, in that chemicals that will attack aluminium oxide will often also attack aluminium.

    If you do manage to get the post out, when you re-fit the seatpost don't rely on carbon fibre grip compound alone to save you from corrosion as it's too easily washed away. Smear the seatpost in a seriously water-resistant grease (e.g. marine grease) then apply a bit of CF grip compound over that in the area that's clamped by the collar.

    Good luck! I hope you manage to save your frame, Shredders_Only.
    Hose me down till the water runs clear.

  3. #3
    Cycologist
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    What anti-seize did you use? I'd try PB Blaster and/or Zep 45; they are better than most of the other oils. Let it soak overnight and repeat a couple of times. And then clamp the seat post in a vise and try to turn the frame. Then add the dry ice and torch method on top of that.

    Good luck, I'm afraid you're going to need it. I wrestled with a steel frame for about a month and finally got it. Torch ruined the paint but I was already planning on having the frame powder coated. It was a $950 frame I picked up for $40 with the stuck post.

    I'm not sure what you mean by "a hole drilled through it"; are you talking about reaming?
    There are two types of people in this world:
    1) Those who can extrapolate from incomplete data

  4. #4
    mtbr member
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    Ahhh---KS strikes again---I had this on my Pivot---in the end I sent the frame back to Pivot and they removed it using some caustic acid----nothing else worked-----lots of people with advice----do a search on this site and the youtube-----you will see guys putting the post in a vice and then twisting the frame.

    KS had a batch of posts that did this and many got stuck----sometime ago.

    I will NEVER buy one of their products again as this was weeks of pain for me

  5. #5
    since 4/10/2009
    Reputation: Harold's Avatar
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    Quote Originally Posted by Shredders_Only View Post
    Iím at the point where Iím certain it has to be cut, a hole drilled through it, and removed that way. However I know my dropper post has an internal air chamber. Anyone have any experience removing a dropper post this way? I want to avoid puncturing the air chamber during removal. Itís an aluminum frame and dropper.
    Yeah, I don't think you want to go that route. If you can't chemically remove it at the recommendations of others, I think you'll likely have to trash both the frame and the dropper, because I don't think you'll be able to cut the post out without puncturing the air chamber, and the risk of flying shards of shrapnel is going to be high with that.

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