Page 78 of 694
SPEC
2 - 3
GENERAL SPECIFICATIONS
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN and ZA)
90/90-21 54R (For EUROPE, AUS and NZ)
Size (rear) 100/100-18 59M (For USA, CDN and ZA)
130/90-18 69R (For EUROPE, AUS and NZ)
Tire pressure (front and rear) 100 kPa (1.0 kgf/cm
2
, 15 psi)
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 315 mm (12.4 in)
Electrical:
Ignition system CDI magneto
Headlight type: Quartz bulb (halogen)
Bulb wattage
×
quantity:
Headlight 12 V 60/55 W
×
1
Taillight 12 V 21/5 W
×
1
Page 162 of 694

3 - 3
INSP
ADJ
MAINTENANCE INTERVALS
* marked : For USAFRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube
●
●
Lithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube
Retighten
●
●
●
●
●
(After
rain ride)
● Molybdenum disulfide
grease
CHAIN GUARD AND ROLLERS
Inspect
● ●
SWINGARM
Inspect, lube and retighten
● ● Molybdenum disulfide
grease
RELAY ARM, CONNECTING ROD
Inspect, lube and retighten
● ● Molybdenum disulfide
grease
STEERING HEAD
Inspect free play and retighten
Clean and lube
Replace bearing
● ●
●
● Lithium base grease
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
Lubricate
●
●
●
●
●
●
●
Lithium base grease
THROTTLE, CONTROL CABLE
Check routing and connection
Lubricate
Inspect and clean (throttle cable)
●
●
●●
●
●
Yamaha cable lube or
SAE 10W-30 motor oil
Inspect dirt and wear on
the throttle cable on the
carburetor side. ItemAfter
break-inEvery
race
Every
third race
or
500 km
(300 mi)Every
fifth race
or
1,000 km
(600 mi)
As re-
quiredRemarks
Page 172 of 694

3 - 4
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 that the coolant level is correct in the coolant reservoir.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-14
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-14 ~ 18
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-9
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-10 ~ 11
Brakes Check the play of front brake and effect of front and rear brake. P.3-26 ~ 32
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-33 ~ 35
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-43 ~ 44
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-44 ~ 45
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-35 ~ 42
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.4-2
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-33
Lubrication Check for smooth operation. Lubricate if necessary. P.3-46
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-18
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
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 ~ 23
Page 254 of 694
3 - 43
INSP
ADJTIRE PRESSURE CHECK/SPOKES INSPECTION AND
TIGHTENING/WHEEL INSPECTION
EC36Q000
TIRE PRESSURE CHECK
1. Measure:
Tire pressure
Out of specification → Adjust.
NOTE:
Check the tire while it is cold.
Loose bead stoppers allow the tire to slip off
its position on the rim when the tire pressure
is low.
A tilted tire valve stem indicates that the tire
slips off its position on the rim.
If the tire valve stem is found tilted, the tire is
considered to be slipping off its position. Cor-
rect the tire position.
Standard tire pressure:
100 kPa (1.0 kgf/cm2, 15 psi)
EC36S002
SPOKES INSPECTION AND TIGHTENING
1. Inspect:
Spokes 1
Bend/damage → Replace.
Loose spoke → Retighten.
2. Tighten:
Spokes
NOTE:
Be sure to retighten these spokes before and
after break-in. After a practice or a race check
spokes for looseness.
T R..3 Nm (0.3 m · kg, 2.2 ft · lb)
EC36T000
WHEEL INSPECTION
1. Inspect:
Wheel runout
Elevate the wheel and turn it.
Abnormal runout → Replace.
Page 666 of 694
7 - 13
TUNSETTING
EC72N000
Drive and rear wheel sprockets setting
parts
Part name Size Part number
Drive sprocket 1
(STD) 13T 9383B-13218
Rear wheel
sprocket
2
(STD)48T
50T
52T
54T5GS-25448-50
5GS-25450-50
5GS-25452-50
5PH-25454-50
EC721002
Tire pressure
Tire pressure should be adjust to suit the road
surface condition of the circuit.
Under a rainy, muddy, sandy, or slippery
condition, the tire pressure should be lower
for a larger area of contact with the road sur-
face.
Under a stony or hard road condition, the tire
pressure should be higher to prevent a flat
tire.
Standard tire pressure:
100 kPa (1.0 kgf/cm2, 15 psi)
Extent of adjustment:
60 ~ 80 kPa
(0.6 ~ 0.8 kgf/cm
2, 9.0 ~ 12 psi)
Extent of adjustment:
100 ~ 120 kPa
(1.0 ~ 1.2 kgf/cm
2, 15 ~ 18 psi)