road-tyre-rim-disc-pads-caliper-forks-headstock [front wheel only of course]
but there is the location of the wheel in space ,i.e. the hub bearings -spindle -forks .which all the above are pivoting on.
so in terms of motion about a point it would be....load-effort-fulcrum . but notice how close the load is to the effort on a rim mounted disc opposed to a hub mounted one,thus increasing the mechanical efficency of the brakes. for the same amount of effort more load can be handled .also the torsional loading between the load and the effort is tremendously decreased due to their closeness.
but the kids love um and so do all them custom boys out there cause they look rad man....
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years