Inspection And Repair - Yamaha Tt-R125Y 2009 Manuel D'atelier

ELECTRIC STARTING SYSTEM
(TT-R125E/TT-R125LWE)
6-14

INSPECTION AND REPAIR

1. Inspect:
• Commutator
Dirt → Clean it with #600 grit sandpaper.
2. Measure:
• Commutator diameter a
Commutator wear limit:
21.0 mm (0.83 in)
Out of specification → Replace the starter
motor.
3. Measure:
• Mica undercut a
Mica undercut:
1.5 mm (0.06 in)
Out of specification → Scrape the mica
to the proper value (a hacksaw blade can
be ground to fit).
TIP
The mica insulation of the commutator must be
undercut to ensure proper operation of
commutator.
4. Measure:
• Armature assembly resistance (commuta-
tor and insulation)
Out of specification → Replace the starter
motor.
Measurement steps:
• Measure the armature assembly resis-
tances with the pocket tester.
Pocket tester:
YU-3112-C/90890-03112
Armature coil:
Commutator resistance 1
0.017 ~ 0.021 Ω at 20 °C (68 °F)
Insulation resistance 2
Above 1 MΩ at 20 °C (68 °F)
• If any resistance is out of specification,
replace the starter motor.
– +
ELEC