Mazda MX-5 Miata Sport 2007 Manual page 1911

2007 Mazda MX-5 Miata Sport
2007 ENGINE Starting System - MX-5 Miata
Fig. 13: Measuring Armature Runout Using Dial Indicator
Courtesy of MAZDA MOTORS CORP.
4. Measure the commutator diameter.
If not within the minimum specification, replace the armature.

Starter commutator diameter
Standard: 29.4 mm {1.16 in}
Minimum: 28.8 mm {1.13 in}