This bit, wont go over the top of the steerer..... I'm guessing I'll need to file down the top into a tiny taper to squeeze it on.... anyone else had this issue? I've warmed the cover, added a dab of grease, but it's just not budging over the top.
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Sometimes the expander bolt expands the steerer tube just enough to stop it coming off, take out the expander bung and see if it then free's it up
Had the same issue with my Hope headset, think the cap is particularly tight. Like you say, take a file to the top of the steerer and taper it ever so slightly and grease the inside of the cap/seal. Worked for me. I was using a SFN so not sure if it'd be Hope's expander thing.
Quite likely if your steerer has been cut and not chamfered, they are tight.
I have the same issue. Its the rubber 'O' ring that sits inside the top cap. Try filing a slight taper on the steerer edge or you could just take the 'O' ring out (which I did on one of mine), it'll be fine! It just presses onto the split wedge to make sure its tight against the top race and the steerer tube.