OK, Having just been quoted NZ$60 for a crappy no-brand single speed converter (you know the things, DMR and Gusset make them: http://www.jensonusa.com/store/product/CS611B00-Gusset+Single+Speed+Conversion+Kit.aspx) And with no apparant way to ship one form the US for less than $40, I have decided to try and make my own. I have an XT cassette I can pull appart for the cogs, and also obviously the lockring, and thanks to Gusset I know the lengths of the spacers I need - 14 and 19mm. So what I need to know from a with a vernier caliper, what is the outside diameter of a standard freehub? Then I can just get down to the local hardware store and pick up a bit of pipe. I already have a pipe cutter. Anyone? I could measure it myself but if you happen to work in a shop and have a decent measuring device, I'd love to know an exact measurement!