Yamaha R1 2004 ServiceManual

8-18

Check the entire starting system’s wiring.
Refer to “CIRCUIT DIAGRAM”.

Is the starting system’s wiring properly con-
nected and without defects?
EAS00766
12. Wiring
YESNO
Properly connect or
repair the starting
system’s wiring.
The starting system
circuit is OK.
11. Start switch

Check the start switch for continuity.
Refer to “CHECKING THE SWITCHES”.

Is the start switch OK?
YESNO
Replace the right
handlebar switch.
EAS00764
10. Clutch switch

Check the clutch switch for continuity.
Refer to...

8-19
STARTER MOTORELEC
Order Job / Part Q’ty Remarks
1
2Removing the starter motor
Seat
Fuel tank
Throttle body assembly
Starter motor lead
Starter motor1
1Remove the parts in the order listed.
Refer to “SEAT” in chapter 3.
Refer to “FUEL TANK” in chapter 3.
Refer to “THROTTLE BODIES” in 
chapter 7.
For installation, reverse the removal 
procedure.
10 Nm (1.0 m
kg, 7.2 ft
lb)5 Nm (0.5 m
kg, 3.6 ft
lb)
5 Nm (0.5 m
kg, 3.6 ft
lb)
EAS00767
STARTER MOTOR 

8-20
STARTER MOTORELEC
Order Job / Part Q’ty Remarks
Disassembling the starter motor
O-ring
Front cover
Lock washer
Washer
Starter motor yoke
Armature assembly
O-ring
Starter motor lead
Brush holder
Rear cover1
1
1
1
1
1
2
2
1
1Disassemble the parts in the order listed.
For assembly, reverse the disassembly 
procedure.
1
2
3
4
5
6
7
8
9
10
5 Nm (0.5 m
kg, 3.6 ft
lb)
5 Nm (0.5 m
kg, 3.6 ft
lb)
5 Nm (0.5 m
kg, 3.6 ft
lb)
EAS00768 

8-21
STARTER MOTORELEC
NOTE:
EAS00770
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.
Commutator wear limit
24.5 mm (0.96 in)
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 commuta-
tor.
Mica undercut
1.5 mm (0.06 in)
The mica of the commutator must be undercut
to ensure proper...

8-22
STARTER MOTORELEC
NOTE: 5. Measure:

brush length 
a.
Out of specification 
 Replace the brushes
as a set.
Brush length wear limit
3.6 mm (0.14 in)
6. Measure:

brush spring force
Out of specification 
 Replace the brush
springs as a set.
Brush spring force
5.28  7.92 N
(538  808 gf, 18.99  28.48 oz)
7. Check:

gear teeth
Damage / wear 
 Replace the gear.
EAS00772
ASSEMBLING THE STARTER MOTOR
1. Install:

brush seat 
1
Align the slot a on the brush seat with the tab b
in the starter motor rear...

8-23
STARTER MOTORELEC
5 Nm (0.5 m
kg, 3.6 ft
lb)
NOTE: 3. Install:

starter motor yoke 
1

O-rings 2 New

starter motor rear cover 
3

bolts 
Align the match marks 
a on the starter motor
yoke with the match marks 
b on the front and
rear covers. 

8-24
2A.C. magneto
3Rectifier / regulator
4Fuse (main)
6Battery
CHARGING SYSTEMELEC
EAS00773
CHARGING SYSTEM
CIRCUIT DIAGRAM 

8-25
NOYES
3. Charging voltage

Set the engine tachometer to the ignition coil
of cylinder #1.

Connect the pocket tester (DC 20 V) to the
battery as shown.
The charging circuit
is OK. Positive tester probe 
 
positive battery terminal
Negative tester probe 
 
negative battery terminal

Start the engine and let it run at approxi-
mately 5,000 r / min.

Measure the charging voltage.
Charging voltage
14 V at 5,000 r / min

Is the charging voltage within specification?
EAS00775
YESNO

Clean the battery...

8-26
CHARGING SYSTEMELEC
YESNO 5. Stator coil resistance

Remove the generator cover.

Connect the pocket tester (Ω 
 1) to the sta-
tor coils as shown.
Replace the stator
coil assembly.
EAS00776
Positive tester probe 
 white 
Negative tester probe 
 white
Positive tester probe 
 white 
Negative tester probe 
 white1
1
2
3

Measure the stator coil resistances.
Stator coil resistance
0.14  0.18 Ω at 20C (68F)

Is the stator coil OK?
YESNO 6. Wiring

Check the wiring connections of the entire
charging...

8-27
LIGHTING SYSTEMELEC
EAS00780
LIGHTING SYSTEM
CIRCUIT DIAGRAM