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I'm completely taking apart a 2014 Kona UTE (for fun, and to clean it, but nothing wrong with it). I'm not sure how to proceed with the fork. It is now "bare" (no wheel, no cable, no handle, no handlebar, nothing), but does not come loose.

enter image description here

The headset is listed (non-officially, but recent models have "FSA N0.10" as well) as being "TH ZST No.10". I believe the full reference is "FSA No.10 Semi Integrated Internal Headset 1-1/8Inches 8.2mm Top Cone ZS44, XTE1600". I'm not familiar with internal headset, so I've looked around:

  • The service doc says nothing about how to install / uninstall it,
  • Some site says that it's "just" supposed to come loose,

Pull fork from bike. It may be necessary to use mallet and tap top of steering column driving fork downward. Once fork is driven down as little as 25mm (one inch), lift fork back up and remove center cone from adjusting race. Remove fork.

enter image description here

But, as of now, the fork does not move, not even one millimeter (I mean, it can spin, but I can't move it up or down).

Am I suppose to force with a mallet gently, or is there something else that needs to be removed before trying to have the fork come loose?

EDIT: some other solutions are suggested here, like "whack[ing] the steerer from the side a couple time", or "a tiny little flat bladed screwdriver in the gap, and carefully pry one edge up". Also, this post gives the terminology quite clearly.

Update: I give up. I've tried many different techniques, and the fork never moved. Since it is not damaged and work properly, I give up, and just leave it like it is.

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This is the compression ring. It does the same thing as the silver one on the Colnago in your picture.

enter image description here

Your fork is stuck because it's wedged in too tight.

You need to whack the top of the steerer hard with something that won't hurt it, and you need to have the fork off the ground while you're doing that. Hit it as though you're trying to send it flying out of the bike. Support the frame under the top tube or down tube with your other hand. You're trying to move the steerer inside the compression ring. Using a rubber mallet or dead blow on the end of a steerer will usually hurt the tool. A block of wood is a good idea. You can tape it on if you run out of hands.

Digging out the ring by putting a screwdriver in the slot can also work, but could also tear it up if it's really tight. There's some advantage to doing it this way if you can because then you're not hammering on your bearings. But it usually doesn't work, and upper headset bearings have an easy life anyway.

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  • Thanks a lot for your detailed and rapid answer. I whacked it numerous times with a rubber mallet and a block of wood, but it didn't moved at all. I can't find a way to dig the ring out. I was wondering if putting some fine oil, for instance, between the tube and the ring, and letting it rest overnight before trying to whack it again would help: what do you think? I'm planning on cleaning and re-greasing everything afterward in any case.
    – Clément
    Jun 20, 2020 at 18:16
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    Penetrating fluid couldn't hurt but may not help a great deal either, since essentially the compression ring is doing its job remarkably well. Are you certain your blows are forceful and landing on the steerer of an unsupported fork? (The frame should be supported at the notch that forms at the lower headtube and downtube junction by something without sharp edges and covered with cloth or rubbery layer. Something to prevent denting the frame from the transmitted force of the blow).
    – Jeff
    Jun 20, 2020 at 23:21
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    Maybe try to bang the steerer UP a few times (hit the underside of the fork crown). Not as much force should be used this way so as to not abuse the lower headset bearings. Couple taps up and a blow or two back down. Just need to get the steerer to come down a fraction of an inch to get space for the whole assembly to come back up and the compression ring out of its seat.
    – Jeff
    Jun 20, 2020 at 23:27
  • Nathan: would snapring pliers in the slot of the compression ring work here or would they simply slip off ?
    – Criggie
    Jun 23, 2020 at 4:00
  • @Criggie I'm not sure I see how to use snapring pliers on it. The idea would be to pry up at the slot. Jun 23, 2020 at 5:38

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