The following is taken from an article entitled, "ITALIAN COMPETITION BRAKES" written by GIANNI PERRONE. I wish to give the author full credit for his wonderful work, and am only reprinting this material to make it accessible to more motorcycle enthusiasts.
Overall view of the front brake (magnesium alloy) used on the MV Agusta 500 racers before they adopted the Ceriani brakes. The two dynamic air intakes are of sheetmetal riveted to the shoe plates.
The four shoes are considerably slotted for lightness. Although there are two shoe plates, the brake has only two cams rather than four.
The two cast-iron ring inserts with the brake "bands" are riveted to the hub (equipped with a central crown").