# Front brake disc minimum thickness — 255 mm rotor

Canonical URL: https://miatatorque.com/spec/front-disc-minimum-thickness-255mm-nb2/

Applicability: NB 2001–2005 (BP-Z3) — Other years in this family inferred from 2005 factory evidence with owner approval; actual-year verification is separate.

Confidence: fsm

18.0 mm (0.71 in)

Always confirm against your factory manual. Match every restriction and follow all stages and procedure notes. Disputed claims must not be automatically resolved. The complete record below preserves every printed unit, source claim and procedure.

```json
{
  "id": "front-disc-minimum-thickness-255mm-nb2",
  "name": "Front brake disc minimum thickness — 255 mm rotor",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NB",
      "years": [
        2001,
        2005
      ],
      "engines": [
        "BP-Z3"
      ],
      "note": "Other years in this family inferred from 2005 factory evidence with owner approval; actual-year verification is separate."
    }
  ],
  "kind": "non-torque",
  "value_text": "18.0 mm (0.71 in)",
  "procedure": {
    "notes": "Applies only to a 255 mm outer-diameter front rotor; confirm the installed factory rotor size. Discard minimum and minimum after machining are separate limits. Machine on the vehicle; do not exceed the discard limit."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-2005",
      "page": "PDF p. 1282",
      "as_printed": "Minimum\nDisk plate outer diameter 255 mm {10.0 in} 18.0 mm {0.71 in}",
      "verified_years": [
        2005,
        2005
      ],
      "document": {
        "id": "fsm-2005",
        "tier": 1,
        "title": "2005 Mazda MX-5 Miata Workshop Manual (electronic manual capture)",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2005,
              2005
            ],
            "engines": [
              "BP-Z3"
            ]
          },
          {
            "gen": "NB",
            "years": [
              2005,
              2005
            ],
            "engines": [
              "BP-Z3-TURBO"
            ],
            "trans": [
              "6MT"
            ]
          }
        ]
      }
    }
  ],
  "jobs": [],
  "system": "brakes",
  "component": "gap-followup-2026-10",
  "componentName": "Additional factory manual gap audit",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/front-disc-minimum-thickness-255mm-nb2/"
}
```