The BB7 Road is designed to work with road bike brake levers and the BB7 mountain is designed to work with off-road brake levers, which as noted in the previous post... have different mechanical advantage. The Mountain version came out first and again, as noted in the earlier post, adapaters were needed to allow the use of a BB7 disc with a road bike that used drop-bar brake levers.
Avid eventually developed a road version that is compatible with drop bar levers and Shimano has also increased the mechanical advantage of their road brake levers which vastly improved overall disc brake ease of set-up and use, as a lot of folks still had a hard time setting up Avid BB7 Road discs with the drop-bar brake levers.
Nowadays, you can easily tell the difference between the Road & Mountain versions as the Road have a (silver) finish and the mountain have a black finish.
Last edited by TandemGeek; 06-26-12 at 02:57 PM.
Reason: Corrected by Chris W. What WAS I thinking....