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EBU00015
1-CONTENTS
LOCATION OF THE WARNING
AND SPECIFICATION LABELS ............. 1-1
SAFETY INFORMATION ......................... 2-1
DESCRIPTION AND MACHINE
IDENTIFICATION ................................... 3-1
Identification number records .............. 3-3
Key identification number .................... 3-5
Vehicle identification number .............. 3-5
Model label ........................................... 3-7
CONTROL FUNCTIONS ........................ 4-1
Main switch........................................... 4-1
Indicator and warning lights ................. 4-3
Handlebar switches ........................... 4-11
Throttle lever ..................................... 4-15
Speed limiter ...................................... 4-17
Clutch lever ....................................... 4-19
Brake lever ......................................... 4-19
Brake pedal ........................................ 4-21
Parking brake .................................... 4-23
Shift pedal ......................................... 4-27
Reverse knob .................................... 4-27
1234
Fuel tank cap .................................... 4-29
Fuel cock ........................................... 4-29
Starter (choke) .................................. 4-31
Seat.................................................... 4-33
Front shock absorber adjustment ...... 4-35
Rear shock absorber adjustment ....... 4-37
PRE-OPERATION CHECKS .................. 5-1
Front and rear brakes .......................... 5-5
Fuel ...................................................... 5-9
Engine oil ........................................... 5-13
Coolant............................................... 5-17
Chain ................................................. 5-19
Throttle lever ...................................... 5-21
Fittings and fasteners......................... 5-21
Lights ................................................. 5-21
Switches............................................. 5-21
Tires .................................................. 5-23
How to measure tire pressure ........... 5-27
Tire wear limit .................................... 5-29
5
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3-1
EBU00032
DESCRIPTION AND MACHINE
IDENTIFICATION1. Seat
2. Fuel tank cap
3. Engine oil tank
4. Brake pedal
5. Headlights
6. Fuel cock
7. Throttle stop screw
8. Coolant reservoir
9. Tail/brake light10. Shift pedal
11. Clutch lever
12. Handlebar switches
13. Parking brake
14. Main switch
15. Reverse knob
16. Throttle lever
17. Brake leverNOTE:The machine you have purchased may differ
slightly from those shown in the figures of this
manual.
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4-29 1. Fuel tank cap
1. Bouchon du réservoir de carburant
1. Tapón del depósito de combustible
EBU00092
Fuel tank cap
Remove the fuel tank cap by turning it counter-
clockwise.
EBU00093
Fuel cock
The fuel cock supplies fuel from the fuel tank to the
carburetor.
The fuel cock has three positions.
OFF: With the lever in this position fuel will not
flow. Always turn the lever to this position
when the engine is not running.
ON: With the lever in this position, fuel flows to
the carburetor. Normal riding is done with
the lever in this position.
RES: This indicates reserve. If you run out of fuel
while riding, turn the lever to this position.
THEN FILL THE FUEL TANK AT THE
FIRST OPPORTUNITY. After refuelling, re-
turn the fuel cock lever to the “ON” position.
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5-9
EBU00998*
Fuel
Make sure there is sufficient gasoline in the tank.NOTE:_ (for Europe only)
If knocking or pinging occurs, use a different brand
of gasoline or higher octane grade. _CAUTION:_ Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system. _
Recommended fuel:
Unleaded gasoline only
For Europe:Regular unleaded gasoline only
with a research octane number
of 91 or higher
Fuel tank capacity:
Total:
12 L
Reserve:
2.6 L
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5-11 1. Fuel tank filler tube
2. Fuel level
1. Tube de remplissage du réservoir de carburant
2. Niveau de carburant
1. Tubo de llenado del depósito de combustible
2. Nivel de combustible
WARNING
_
Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is over-
filled, fuel could spill out due to heat from
the engine or the sun.
Be careful not to spill fuel, especially on
the engine or exhaust pipe which can
cause a fire and severe injury. Wipe up any
spilled fuel immediately.
Do not refuel right after the engine has
been running and is still very hot.
Be sure the fuel tank cap is closed secure-
ly.
_
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8-125
EBU00724
Troubleshooting chart
Starting problems or poor engine performance1. Fuel
Check if there is fuel
in the fuel tank.There is fuel.Turn the fuel cock
lever to “OFF”.No fuel.Fuel cock is
clogged.
Clean the
fuel cock. Some fuel.Turn the fuel cock
lever to “RES”.Restart the engine.
No fuel.Supply fuel.
2. Compression
Use the electric
starter to see if
there is compression.There is compression.
Compression normal.
No compression.Ask a Yamaha dealer to
inspect.
3. Ignition
Remove the
spark plug and
check electrodes.WetWipe clean with dry cloth.
DryAttach spark plug cap and
ground to chassis.Use the
electric starter.Spark is good.Ignition system is
normal.
Spark is weak.
Adjust the spark plug gap
or replace the spark plug. No spark.
Ask a Yamaha dealer to
inspect. 4. Battery
Use the electric starter.Engine turns over
quickly.Battery is good.
Engine turns over
slowly.Check the connections.Check the
fuel flow.
Turn the fuel cock
lever to “ON”.
Remove the fuel hose
from the fuel cock.
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10-3
Radiator capacity (including all routes) 1.3 L
Air filter Wet element
Fuel:
Type
Tank capacity
Reserve amountUnleaded gasoline only
For Europe: Regular unleaded gasoline only with a
research octane number of 91 or higher
12 L
2.6 L
Carburetor:
Type
× quantity
ManufacturerBSR33
× 2
MIKUNI
Spark plug:
Type/manufacturer
GapDPR8EA-9/NGK
0.8–0.9 mm
Clutch:
Type
OperationWet, multiple-disc
Left hand operation
Transmission:
Primary Reduction System
Primary Reduction Ratio
Secondary Reduction System
Secondary Reduction Ratio
Transmission type
OperationSpur gear
71/34 (2.088)
Chain drive
40/13 (3.076)
Constant mesh, 5-speed forward, 1-speed reverse
Left foot operation MODEL YFM660R
U5LP63.book Page 3 Monday, March 10, 2003 2:06 PM