Originally Posted by dabac

Makes perfect sense. Cutting holes in something meant to take an internal expander seems rather risky.
S




The steerer began as a tube.
It might be widened in spots, by enthusiastic tightening of previous quill stem wedges.
But an accidental taper - not very likely.
Maybe the ID is overall a little wide, and maybe the OD of the adapter is overall a little narrow.


I'd still start by Another look at the headset, a far more common cause for play in this area.