Two excellent ideas, thank you very much. Of course, if I miss out four holes on each side of the hub, then it's a 32 hole hub, albeit with irregular hole spacing. I haven't been able to get the Sun CR18 in 590 with 40 holes in Europe. This guy will ship to the EU, but there are always customs complications.
http://www.ebay.co.uk/itm/Sun-CR-18-...ht_2140wt_1062
but if I can use a 32h rim, which are much more common, that solves everything. I was feeling a bit despondent and thinking about just getting a built up 3 speed here:
http://www.freemanscycles.co.uk/bicy...ear-wheel.html
But now I'll look for a suitable 32 hole rim instead. So what is the optimum size? Perhaps 650B (584 mm iso) is a better choice than 590mm?
cheers
Duncan