Thanks, spambait11.

The referenced article does inspire! The only problem is that the clamp that he uses to secure the headset is not quite what I had in mind ... still, it does give me some ideas. What I had in mind was some sort of headset that had built-in set screws that would press against the fork's steerer tube, thus eliminating the need for a separate clamp.

The catch here is that I want to avoid too much stack height on the upper part of the headset. Right now I have a budget, non-adjustable Dahon handlepost (the "Revolve" (???)) that is chopped off at the top (with a pipe cutter ...). To attach the stem (and the drop handlebar), I inserted a 1 1/8 in. quill aheadset adapter. For reasons not worth mentioning here, I can't chop off any more of the handlepost.

But the fact that a separate clamp is needed does not need to be a problem. The clamp that is used in the article is a good 1.5 to 2 in. high, with two clamp bolts. For my application, I think that it could be replaced with a simple seat clamp, which could be 1/2 in. high or shorter.

Worst case, if I need to use a wide clamp and, as a result, the stack height is too high, I can buy an adjustable Dahon handlepost. That way, I don't need to worry about stack height, because I can adjust the stem downward, thus ending up with the same handlebar height.

The next challenge is to find a 20 in. chromoly fork with 1 1/8 in. threadless steerer that is not a BMX fork !