I'm also using the speed dial lever with MTN BB7.. on Trekking Bars.. (22.2 | 7/8" like MTB bars)

One difference I glean from the Avid exploded parts diagram .. is the actuating ring, that turns the rotary motion

into the sideways pressure that pushes the pad against the disk, the ring is crown like , a number of ramps, that do the pushing.

Road version, the ramps in the crown ring are steeper angled than those on the MTB version..


Paul's USA made "Clamper" mechanical disc caliper , uses a different length of actuating arm but the internals are all the same.