1. Make sure the disc code number corresponds
to the vehicle on which it will be installed.
2. Always replace both discs on each axle at
the same time.
3. Read and scrupulously follow the
instructions for disc replacement.
4. Replace discs the moment they show signs
of deep grooves, uneven wear or when they reach their minimum thickness.
5. Minimum thickness is indicated on every
disc (for instance, MIN. TH 37 mm indicates a minimum thickness of 37 mm). This
value is also given in the Brembo catalogue. Generally speaking a brake disc
will wear down over the period of 2-3 pad changes.
6. Carefully clean discs before installation.
Check that there are no traces of oil or grease on the braking surfaces. This
could negatively affect braking performance.
7. Once the disc is fitted, check it with a
run-out gauge attached to the suspension arm. Measure disc run-out on the
outside section of the braking surface. After one complete turn of the wheel the
run-out value must not exceed 0.12 mm. If the value is greater, change the
position of the disc with respect to the wheel hub (if the positioning holes
allow this) or fit the second disc. Disc run-out measurement is a very important
operation. If run-out is excessive, over time and after a few thousand
kilometres the disc may show abnormal wear, even in the absence of braking
action (caused by partial contact with the pads), and vibrations may be felt
when braking. The maximum run-out tolerance indicated by Brembo has been
determined on the basis of our experience. Some commercial vehicle manufacturers
may indicate slightly different values. In such cases, the value indicated by
the latter should be used.
8. Adopt a brief running-in period for new
discs (about 500 km). During this period braking should be regular and smooth to
allow the disc and pads to bed in correctly. Over sharp or too prolonged a
braking action could cause the pad friction material and disc to overheat, with
the risk of compromising brake performance over the long term.
9. Discs and pads are important sources of
information (state of surfaces, colour, appearance). Any change in their
condition could indicate breakage or wear of one or more components on the axle
(calipers, hub, bearings, etc.).