Had to fit this adapter where was the quill stem. Tried putting spacers but because it is narrower at the base they kept moving. Is that dangerous? (other than being dangerously ugly?) :
How To Convert Quill Stem To Threadless Stem With Adapter On Vintage Bike - YouTube
22.2/25.4mm Bike Quill Stem Adapter Extender Riser Adaptor Aluminum Black Silver | eBay