Mine was quite badly corroded and the allen key was rounded off. I had to cut the top of the bolt/stem off with a grinder. Then cut a bit more of the outer tube of the stem away so I could get at the bolt with a hammer. Got it out eventually.
@Greggbell started
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Mine was quite badly corroded and the allen key was rounded off. I had to cut the top of the bolt/stem off with a grinder. Then cut a bit more of the outer tube of the stem away so I could get at the bolt with a hammer. Got it out eventually.