Found some pics of the R20 that Jur built awhile back and love the look of it. I have searched the Folding Bike forum for his parts list but cannot find it. Jur, is there a link to a list of parts that you used?
Sheldon states on one of his pages that the R20 headset is a standard size and that any 1" headset should fit. Well, I purchased two Ritchey Logic 1" sets, threaded and threadless, but both are too large to fit in the head tube of my R20. Not by much, but the LBS did not want to try to press them in since the head tube is not reinforced. The difference in O.D. of the headsets is only .01, but you can tell it would be a squeeze to get them in. Some judicious grinding might be in order here.
Jur appears to have used a threadless setup. What headset did you use? Were there any fitting problems? Where did you get the super long steerer tube? I have a local source for Chro-moly tubing that can be cut to length. I am planning to buy a section from them if I find a suitable headset.
What headset and steerer tubes have others used? Again, any problems fitting the parts into the head tube?
Thanks for your help!