Wonky headset Cap

[Becky]

Your shop should have the right tool to reset it, and it's a 2-minute job. IME, the tool really does make it easier to set the star nut straight and at the correct depth.

I would be concerned about why it moved in the first place. I've never seen that happen.

[DebW]

Is your stem loose or moving upward on the steerer column? If the stem were properly tighten, there should be almost no pressure on the star nut and top cap. Has the headset been feeling loose or jiggling?

[beany]

I would be concerned about why it moved in the first place. I've never seen that happen.

I slipped on some mud coming round a corner, and fell onto a low wall. When I checked my bike the next day the bolt on the headset was sticking up and the handle bars loose . I should have take off the cap and looked but was in a silly rush so I just tightened the bolt. It must have just been the awkward fall ... combined with the above careless maintenance.

I have tapped the starnut back in following the instructions linked to this thread. I will check it, to make sure it dosent move, if it does or gets grumpy in any way I will visit my LbS,

Thanks everyone for the help