Replacing headset bearings

[Brucey]

if the steerer is damaged internally (which could have caused the bung to move, or damage could have been caused by driving the bung downwards) then there is an appreciable risk that the top of the steerer may just snap off at some point in the future when you are riding the bike. This is almost certain to result in an unplanned hospital visit or failing that a wooden box.



The kinds of bungs that are normally fitted to CF steerers are grippy on the outside and usually have a hollow expander bolt fitted (that accepts an 8mm allen key for example). Typically what happens is that the M6 top cap bolt isn't greased well enough and when you unscrew it the hollow bolt below it starts to undo, loosening the bung. Or the bung can loosen for other reasons, like the steerer is damaged. It is (IME) very unlikely that there ought to be a bung that is just a push-fit into the top of the steerer, and if there is such a thing fitted, it is very likely not meant to be there.

I would say +1 to peetee's suggestion that you get the thing properly checked out.

cheers

[peetee]

I see a lot of Boardman bikes with poorly adjusted bearings and steering systems. I know they have only ever been serviced at the point of sale so it doesn't give me any confidence that there is a consistent skill level present at that retailer. It looks very much like poor assembly has compromised the integrity of your steering.
It's not fit to ride, POTENTIALLY DANGEROUS and should be assessed by a competent, experienced individual.