Page 24 of 900

CHAPTER 6
ELECTRICAL
ELECTRICAL COMPONENTS
AND WIRING DIAGRAM............ 6-1
MAP-CONTROLLED
CDI UNIT.................................... 6-3
IGNITION SYSTEM.................... 6-8
ELECTRIC STARTING
SYSTEM................................... 6-21
CHARGING SYSTEM.............. 6-45
THROTTLE POSITION
SENSOR SYSTEM................... 6-53
LIGHTING SYSTEM................. 6-67
SIGNALING SYSTEM.............. 6-75
CHAPTER 7
TUNING
ENGINE...................................... 7-1
CHASSIS.................................. 7-21
CHAPITRE 6
PARTIE
ELECTRIQUE
COMPOSANTS ELECTRIQUES
ET SCHEMA DE CABLAGE........ 6-2
BOITIER CDI COMMANDE PAR
PRESSION ABSOLUE DE LA
TUBULURE D’ADMISSION......... 6-4
SYSTEME D’ALLUMAGE............ 6-9
DEMARRAGE ELECTRIQUE... 6-21
SYSTEME DE CHARGE............. 6-46
SYSTEME DU CAPTEUR DE
POSITION DE PAPILLON DES
GAZ................................................. 6-54
ECLAIRAGE................................. 6-68
SYSTEME
DE SIGNALISATION................... 6-76
CHAPITRE 7
MISE AU POINT
MOTEUR......................................... 7-1
CHASSIS........................................ 7-21
Page 37 of 900

1 - 12
GEN
INFO
SPECIAL TOOLS
YS-1880-A, 90890-01701 Sheave holder
This tool is used for when loosening or tightening the
flywheel magneto securing nut.
YU-3112-C, 90890-03112 Pocket tester
Use this tool to inspect the coil resistance, output
voltage and amperage.
YM-33277-A, 90890-03141 Timing light
This tool is necessary for checking ignition timing.
YM-4019, 90890-04019 Valve spring compressor
This tool is needed to remove and install the valve
assemblies.
YM-91042, 90890-04086 Clutch holding tool
This tool is used to hold the clutch when removing or
installing the clutch boss securing nut.
YM-4111, 90890-04111
YM-4116, 90890-04116Valve guide remover
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
This tool is needed to remove and install the valve
guide.
YM-4112, 90890-04112
YM-4117, 90890-04117Valve guide installer
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
This tool is needed to install the valve guide.
YM-4113, 90890-04113
YM-4118, 90890-04118Valve guide reamer
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
This tool is needed to rebore the new valve guide.
YM-04141, 90890-04141 Rotor puller
This tool is used to remove the flywheel magneto.
Part number Tool name/How to use Illustration
90890-03112
90890-04111
90890-04116
90890-04141
Page 38 of 900
1 - 13
GEN
INFO
SPECIAL TOOLS
YM-34487
90890-06754Dynamic spark tester
Ignition checker
This instrument is necessary for checking the ignition
system components.
YB-35956-A, 90890-06756 Vacuum/pressure pump gauge set
This tool is used to check the air induction system.
90890-85505 YAMAHA Bond No. 1215
(ThreeBond
® No. 1215)
This sealant (Bond) is used for crankcase mating
surface, etc.
Part number Tool name/How to use Illustration
90890-06754
YB-35956-A90890-06756
Page 96 of 900
GENERAL SPECIFICATIONS
2 - 3
SPEC
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 305 mm (12.0 in)
Electrical:
Ignition system CDI
Generator system AC magneto
Battery type YTX5L-BS
Battery voltage/capacity 12 V/4 AH
Specific gravity 1.320
Headlight type: Quartz bulb (halogen)
Bulb wattage × quantity:
Headlight 12 V 60/55 W × 1
Taillight 12 V 21/5 W × 1
Page 110 of 900

MAINTENANCE SPECIFICATIONS
2 - 17
SPEC
EC212300
ELECTRICAL
Item Standard Limit
Ignition system:
Advancer type Electrical ----
CDI:
Pickup coil resistance (color) 248 ~ 372 Ω at 20°C (68 °F)
(White – Red)----
CDI unit-model/manufacturer 5UM-B0/YAMAHA (For USA) ----
5UM-C0/YAMAHA (Except for USA) ----
Ignition coil:
Model/manufacturer 5UL-10/DENSO ----
Minimum spark gap 6 mm (0.24 in) ----
Primary coil resistance 0.08 ~ 0.10 Ω at 20 °C (68 °F) ----
Secondary coil resistance 4.6 ~ 6.8 kΩ at 20 °C (68 °F) ----
Charging system:
System type AC magneto ----
Model (stator)/manufacturer 5UM 20/YAMAHA ----
Normal output 14 V/120 W at 5,000 r/min ----
Charging coil resistance (color) 0.288 ~ 0.432 Ω at 20 °C (68 °F)
(White – Ground)----
Lighting coil resistance (color) 0.224 ~ 0.336 Ω at 20 °C (68 °F)
(Yellow – Ground)----
Rectifier/regulator:
Regulator type Semiconductor short circuit ----
Model/manufacture SH712AC/SHINDENGEN ----
Regulated voltage (AC) 13.0 ~ 14.0 V ----
Regulated voltage (DC) 14.1 ~ 14.9 V ----
Rectifier capacity (AC) 12 A ----
Rectifier capacity (DC) 8 A ----
Electric starting system:
Type Constant mesh ----
Starter motor:
Model/manufacturer 5UM01/YAMAHA ----
Operation voltage 12 V ----
Output 0.35 kW ----
Armature coil resistance 0.0189 ~ 0.0231 Ω at 20 °C (68 °F) ----
Brush overall length 7 mm (0.28 in) 3.5 mm (0.14 in)
Brush quantity 2 pcs. ----
Spring force 3.92 ~ 5.88 N
(400 ~ 600 g, 14.1 ~ 21.2 oz)----
Commutator diameter 17.6 mm (0.69 in) 16.6 mm (0.65 in)
Mica undercut (depth) 1.5 mm (0.06 in) ----
Page 192 of 900

SPEC
2 - 99
CABLE ROUTING DIAGRAM
ÊFasten the diode (at the white tape), rectifier/regulator lead,
CDI unit lead (at the protecting tube) and AC magneto coupler
(connected to the CDI unit).
ËFasten the wire harness, coolant reservoir hose, hot starter
cable, negative battery lead and starter motor lead.
ÌFasten the wire harness, negative battery lead, starter motor
lead and coolant reservoir hose at the white tape for the nega-
tive battery lead.
ÍFasten the wire harness at its white tape.
ÎFasten the wire harness, starter motor lead and negative bat-
tery lead.
ÏMake sure that the throttle position sensor coupler does not go
outside the chassis.ÐFasten the throttle position sensor lead.
ÑPass the carburetor breather hoses, carburetor overflow hose
and coolant reservoir breather hose between the connecting
rod and cross tube (frame).
ÒFasten the neutral switch lead and oil hose together with the
plastic locking ties and cut off the tie ends.
ÓFasten the neutral switch lead.
ÔFasten the neutral Aswitch lead and AC magneto lead.
ÕPass the starter motor lead in front of the radiator hose 4.
ÖFasten the wire harness, starter motor lead and negative bat-
tery lead so that the plastic locking tie ends do not contact the
ignition coil lead.
B
B
B-B
A
Ô3B
Ó3 Ö
C
× EF
9
GÙ
H
Ú
Û
1
È
3
Ê
4
Ë
5
6
7 Ì
ÍÎ
Ï
Ñ Ð
8
0 3
ÒÜ II
JK
9 A 2
É
0
9A
ØD ØD
Õ
Page 196 of 900
SPEC
2 - 103
CABLE ROUTING DIAGRAM
1Hot starter cable
2Throttle cable (return)
3Throttle cable (pull)
4Cable guide
5Ignition coil
6Coolant reservoir breather hose
7Coolant reservoir hose
8Clamp
9CDI unit lead
0CDI unit
ACDI unit band
BCDI unit stayÈPass the throttle cables and hot starter cable through the cable
guides.
ÉPass the throttle cables and hot starter cable between the radi-
ator and frame, then under the radiator mounting boss.
ÊPass the throttle cables on the outside of the ignition coil.
ËPass the carburetor breather hose (of the throttle cable cover)
through the hose holder.
ÌFasten the coolant reservoir breather hose and carburetor
breather hoses together.
A B
0
A
0
891
32
4
É
Ê
5
67
Ë ÌÎ
ÍÈ
Page 223 of 900

3 - 16
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.P.3-21 ~ 29
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-49
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-39 ~ 47
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-29 ~ 31
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-31 ~ 33
Brakes Check the play of front brake and effect of front and rear brake. P.3-65 ~ 77
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-79 ~ 83
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-99 ~ 101
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-101 ~ 103
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-85 ~ 97
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or when
the front forks travel up and down.—
Exhaust pipeCheck that the exhaust pipe is tightly mounted and has no
cracks.P.4-7 ~ 11
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-77
Lubrication Check for smooth operation. Lubricate if necessary. P.3-105
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-59
Lead connectorsCheck that the AC magneto, CDI unit, and ignition coil are
connected tightly.P.1-9
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 40