Update - so today I collected a used F500 (2k I think) with a Fatty Super (seller described as 'smooth, no probs) - and not only is it borked (grinding, bottoming out, headset bearings knacked, big split in rubber boot) but this model has no lockout function evident (just a plastic top cap with no lever)
Now what, arghhhhhhhhhhh looks like an expensively cheap purchase this is the second badly described bike I've purchased in one week, and actual riding seems like a distant dream... x(. Tho in the spirit of retro biking I plan to get this thing built up nicely as the frame is actually ok, just the rest of it...