In manufacturing the brake rotor, tolerances of the braking
surfaces are closely held for the following conditions:
The maintenance of close tolerances on the shape of the braking surfaces
is necessary in order to prevent brake roughness or pulsation.
In addition to these tolerances, the surface finish must be held to
a specific range. This range is 60 Ra roughness or less. The control
of the braking surface finish is necessary in order to avoid the following
problems:
Control of the surface finish may improve the lining life. Light scoring
of the rotor surfaces not exceeding 1.5 mm (0.06 in) in depth,
which may result from normal use, is not detrimental to brake operation.