Showing specs for all NA & NB Miatas

Rear brake disc thickness — minimum (NB1)

0.31 in (8.0 mm) minimum8.0 mm {0.31 in} minimum

Factory manualTaken from a Mazda factory workshop manual, with page citation.
Procedure

Discard limit, separate from minimum after machining. Applies to original factory brake equipment for this family; identify installed brake hardware before use.

Applies to
  • NB 1999–2000 (BP-4W) — Other years inferred from 1999 factory evidence.
  • Verified in: 1999 Mazda MX-5 Miata Workshop Manual