I'm still in the dark about new BMX technology... come to think of it, I never learned much about OS tech either! Would a threadless fork and stem fit into a vintage frame? If so, what kind of headset would I need?

My plan is to mate a Kappa fork and stem into a real Hutch Pro Racer frame. Possible?

I'm not sure if it's all inclusive, but new-school forks are 1 1/8", and old-school is 1". Won't work. Best bet there is to get a Kappa frame as well - and sticker it up like a Hutch. Blaspheme? Maybe. Fun? You bet!

1 1/8" threadless forks will fit in a 1" frame. You need to mix parts from 1" and 1 1/8" threadless headsets to accomplish this.

Raybeard had documented it many years ago. Maybe he'll chime in.

Really? Dang, my bad! I'd love it if he'd chime in. I suppose a combination of parts makes sense - but which ones?

Actually, I've done this before. It was awhile back during the switch-over between standards, and I had a GT Robinson that I liked using for street, that I put some 1 1/8" Pitchforks on. (The forks must've weighed as much as the frame.) The guys at Dan's, slag them if you will, built me up a custom headset. Here's how it worked:

Cups from a 1" unsealed headset.
Loose ball bearings. By "loose" I mean no race whatsoever. These were also slightly smaller than the bearings that would've been in the race of a BMX headset. Maybe they were a road bike size...you might be able to get a road bike headset and pop the bearings out of the race. If not, you can probably get them at some kind of industrial "we sell bearings" type of place.

Fork crown race and uppers from a threadless headset, plus star nut, etc.

The loose bearings are a bit of a pain in the but, especially if you've got to take it apart for whatever reason. Just use some nice grease like Phil Wood, set the bearings in the grease, and put it together. It'll work just fine.

It can be done. My XL24 has threadless Schwinn forks with a beefy GT stem (Original Hutch fork bent).