Folder threaded to threadless- with stock fork?
 

Apologies if this has been hashed out before, but I don't see quite what I'm looking to do in the forums, so please humor me. I'd like to be able to separate my xootr swift frame to the main tube, rear triangle, and fork for flying. I know you can just barely wedge it into an f'lite without doing so, but I can fit more stuff in the case with the bike fully apart and also cushion it better this way.

But I really don't want to deal with the threaded headset- regreasing the bearings, packing two large cone wrenches, etc- every time I pack and unpack. I've also read plenty on here about the struggles of finding a threadless fork for the swift that doesn't open pandora's box of BB height, custom stem riser mods, etc.

So why not convert the stock stem to threadless? I'm envisioning using the Sheldon Brown method with a pinch bolt collar to hold the preload tension, but also using spacers to get the stack height up tight to the riser when it's clamped on for extra insurance.

I know Sheldon says it's a Very Bad Idea on a regular bike, because you don't want the stem supported by the weaker, threaded portion of the steerer. But what about the folder where you're already using a QR to clamp a really tall riser to the steerer above the threads? In this case it seems that the steerer is already over-built enough to handle being torqued around above the threads, and the device you are using to keep the spacers snugged up against the headset bearings to maintain their adjustment (i.e. threaded on vs clamped on) shouldn't matter all that much. Unless it's really that bad of an idea to clamp a collar onto the threads and I'm just lacking the imagination to see why.

Any thoughts? Anyone already try it?

So why not convert the stock stem to threadless? I'm envisioning using the Sheldon Brown method with a pinch bolt collar to hold the preload tension, but also using spacers to get the stack height up tight to the riser when it's clamped on for extra insurance.



Any thoughts? Anyone already try it?[/QUOTE]

It's not a good idea. A collar clamped on the steerer will not provide the micro-adjustment you need to hold a good headset adjustment setting. The threaded headset will keep a good adjustment, and the threadless headset really needs the star-fangled nut in the steerer tube to do the same.
Even if you tapped it in place and clamped it down as firmly as you could, it wouldn't take many miles before it slipped enough to have the headset loosen.
I know because a bike I made relies on this type of headset arrangement. I had to make a pinch-bolt collar that incorporates 2 set-screws to keep it there. That solved my issue; the collar does not move any more. But I would not want to take it apart unless necessary for an overhaul or replacement.

A threadless fork requires a longer steer tube than a threaded fork as it has to provide a place for the stem to clamp to. That is the reason it will not work. Roger

Do Rinko bikes have this same issue? And if so, how do they solve it?

Keyed headset washers, fancy 32mm sockets using allen keys for leverage, and cartridge bearings. Jan Heine has a blog post about it, an easy search.