I have read of a mixed use thread less headset on the portion of the fork not threaded .. that makes sense ,,
then your spacers and a through threaded nut ant the top nut to lock against each other..

quill stem is long enough to support the threaded end from the inside.. I got out thr threading die and cut more thread
as it happened I needed a little welding on the head tube..

being threaded so long the fork was its own headset press .. to put it back together again .. & i continued my tour for another 6 months..



I have a King No thread on my Bike Friday Tikit They use a conic ring and clamp set ; as you tighten the pinch bolt its tapered inner face forces the conic ring downward

providing the pre-load folding steering mast has a quill, it goes in the fork, & when its folded down you have the wedge bolt head access,, the top part backs up the expanding clamp ring

On the New BF bikes they use a 2nd clamp ring, to back up the expanding one... those, the Mast above is removable for travel pack size reduction..




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