You can buy them from Ducati for not many £'s. It'll probably be tough to get one from Halfords etc. as they need to be quite thin to get onto the hub.
The Ducati do isn't very good IMHO. It's two piece and made to make if portable, i.e. part of the toolkit. How often do you adjust your chain tension while away from home?
These guys do a much improved version, which is what I use. Just a thought.
Linear Mode
