Originally Posted by
klhada
hmm, would a single cog from a cassette and a normal road chainring work properly if I got a nice tension on the chain? Later on I can always buy optimal parts (like a narrow wide chainring and a single speed cog), but just to get it running, the former option is cheap and fast
Yes, this works. One sees people riding around on single speed conversions of this nature. It's one way of dealing with a bike that is functional except for a trashed drivetrain. Someone sells a kit of spacers that lets you remove all but one of the cogs on a cassette, otherwise you can just leave them there.