Showing specs for all NA & NB Miatas

Front brake disc thickness variation limit

0.015 mm (0.00059 in), maximum

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

Clean the friction surface, measure the factory circumferential points and subtract minimum thickness from maximum. Preserve the applicable rotor minimum when machining.

Applies to
  • NB 2001–2005 (BP-Z3) — Other years in this family inferred from 2005 factory evidence with owner approval; actual-year verification is separate.
  • NB 2004–2005 (BP-Z3-TURBO, 6MT) — Common 2005 front-brake inspection covers both rotor sizes. Diameter-specific limits apply only to the rotor diameter named in the record; 2004 is inferred.
  • Verified in: 2005 Mazda MX-5 Miata Workshop Manual (electronic manual capture)
Sources
  • 2005 Mazda MX-5 Miata Workshop Manual (electronic manual capture)Tier 1
    Page PDF p. 1282
    Printed: “Thickness variation limit 0.015 mm {0.00059 in}”

Also in Additional factory manual gap audit