Originally Posted by
luker
I should just stay away. You guys always get me going. A 14 speed rohloff would replace, quite thoroughly, my current mountain bike setup, and give me almost the same range, and more gears without overlap, nearly the same jump between cogs. Geez.
Does anyone know why you need a chain tensioner with this setup?
It's the chain tension thing. If you have horizontal dropouts, you can move your wheel forward or backward a little and get the chain tension right. If you have vertical dropouts you don't have that option, so typically you need to put some tension on the chain. Alternately you may get lucky with the right combination of chain ring, cog, and a chain of exactly the right length.