A-Stem conversion (Help)

[MontyWoo]

Hello,

I've been a long-time lurker on this forum, but I decided to join today because I need help with a problem that is driving me insane.

I have two pairs of forks: a Columbus Minimal fork and a pair of stainless steel forks. Both have 1-inch external diameter steering tubes and are threadless. I have bought a Deda quill stem adaptor as recommended for using a modern stem and bars. My problem is that on both forks, the internal diameter of the steering tube is too small and will not accept the Deda quill stem adaptor. There is no way it will fit inside the steering tube. It's not just a matter of its tight fit; the quill will not fit at all. Any ideas on how I get around this and has this problem been seen before?

TIA

[Beebsta]

Measure the internal diameter of those forks as I suspect they might have 21 mm ID. This is what you would need
https://www.amazon.com/Silver-Aluminum- ... B08P1JPP4Y