That's the main question, if it's a freehub or freewheel... As I really need to have everything before I start I might be best off getting a single sprocket (since I don't want to use one from the actual cassette) as well as a single speed freewheel (BMX style). Doesn't seem to expensive.

So another question would be, which sprocket for a freehub should I get? Been looking at this Surly sprocket (surlybikes.com/parts/fixed_cogs) but pretty sure it wouldn't fit on a freehub. Any suggestions?

Also found this photo, not sure if it helps in trying to determine if it's a freehub or freewheel...



Cheers,
H