Yamaha R15 2022, Service Manual

Page: 276 / 497

5-39
ELECTRIC STARTER
ENG
EAS30325
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.
TIP
The mica of the commutator must be undercut to
ensure proper operation of the commutator.
4. Measure:
• Armature assembly resistances (commutator
and insulation)
Out of specification
→
Replace the starter
motor.
a. Measure the armature assembly resis-
tances with the multimeter.
b. If any resistance is out of specification, re-
place the starter motor.
5. Measure:
• Brush length “a”
Out of specification
→
Replace the starter
motor front cover/brush holder set.
6. Measure:
• Brush spring force
Out of specification
→
Replace the brush
springs as a set.
7. Check:
• Gear teeth
Damage/wear
→
Replace the gear.
8. Check:
• Bearing
Commutator diameter limit
16.6 mm (0.65 in)
Mica undercut (depth)
1.35 mm (0.05 in)
a
G088985
Multimeter
INS-003
(90890-03189)
Armature coil resistance
0.028–0.034
Ω
Brush overall length limit
3.5 mm (0.14 in)
Brush spring force
3.92–5.88 N (400–600 gf, 14.11–
21.17 oz)
G088987
G088989
BCWF8197E0.book Page 39 Thursday, November 18, 2021 9:18 AM