Checking The Starter Motor - Yamaha YZF-R1P Service Manual

ELECTRIC STARTING SYSTEM
EAS00769

CHECKING THE STARTER MOTOR

1. Check:
• commutator
Dirt → Clean with 600-grit sandpaper.
2. Measure:
• commutator diameter a
Out of specification → Replace the starter
motor.
3. Measure:
• mica undercut a
Out of specification → Scrape the mica to
the proper measurement with a hacksaw
blade that has been grounded to fit the
commutator.
NOTE:
_
The mica of the commutator must be undercut
to ensure proper operation of the commutator.
4. Measure:
• armature assembly resistances (commuta-
tor and insulation)
Out of specification → Replace the starter
motor.
M MMM
a. Measure the armature assembly resis-
tances with the pocket tester.
b. If any resistance is out of specification,
replace the starter motor.
L LLL
8 - 20
ELEC
Commutator wear limit
23.5 mm (0.93 in)
Mica undercut
1.5 mm (0.059 in)
M MMM M M MMM M M MMM M M MMM M
Pocket tester
YM-03112
Armature coil
Commutator resistance 1
0.009 ~ 0.011 Ω at 20 °C (68 °F)
Insulation resistance 2
Above 1 MΩ at 20°C (68 °F)
L LLL L L LLL L L LLL L L LLL L
– +
M MMM M MMM
L LLL L LLL