engine YAMAHA GRIZZLY 660 2004 Owners Manual
Page 16 of 444
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 ............... 3-7
Model label ........................................... 3-9
CONTROL FUNCTIONS ......................... 4-1
Main switch........................................... 4-1
Indicator and warning lights.................. 4-3
Speedometer unit ................................. 4-9
Fuel gauge ......................................... 4-15
Handlebar switches ............................ 4-17
Throttle lever ...................................... 4-35
Speed limiter ...................................... 4-37
Front brake lever ................................ 4-39
Rear brake pedal and lever ................ 4-41
Drive select lever ................................ 4-43
Recoil starter ...................................... 4-43
1234
Fuel tank cap ..................................... 4-45
Fuel cock............................................ 4-47
Starter (choke) ................................... 4-49
Seat.................................................... 4-51
Storage compartment ........................ 4-53
Front carrier ....................................... 4-53
Rear carrier ........................................ 4-53
Front and rear shock absorber 
adjustment ....................................... 4-55
Auxiliary DC jack ................................ 4-59
PRE-OPERATION CHECKS ................... 5-1
Front and rear brakes .......................... 5-7
Fuel .................................................... 5-11
Engine oil ........................................... 5-15
Final gear oil ...................................... 5-17
Differential gear oil ............................. 5-19
Coolant............................................... 5-19
Throttle lever ...................................... 5-21
Fittings and fasteners......................... 5-21
Lights ................................................. 5-23
Switches............................................. 5-23
Tires ................................................... 5-25
How to measure tire pressure ............ 5-29
5
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Tire wear limit......................................5-31
OPERATION ............................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine .........................6-9
Warming up...........................................6-9
Drive select lever operation and 
reverse driving ..................................6-11
Engine break-in ...................................6-17
Parking ................................................6-19
Parking on a slope ..............................6-21
Accessories and loading .....................6-23
RIDING YOUR ATV..................................7-1
Getting to know your ATV .....................7-3
Ride with care and good judgement .....7-5
Be careful where you ride ...................7-27
Turning your ATV ................................7-39
Climbing uphill.....................................7-45
Riding downhill ....................................7-55
Crossing a slope .................................7-59
Crossing through shallow water ..........7-63
Riding over rough terrain ....................7-69
Sliding and skidding ............................7-71
What to do if ........................................7-75
What to do...........................................7-75
67
PERIODIC MAINTENANCE AND 
ADJUSTMENT ......................................... 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Panel removal and installation............ 8-15
Engine oil and oil filter cartridge ......... 8-33
Final gear oil ....................................... 8-47
Differential gear oil.............................. 8-51
Cooling system ................................... 8-57
Changing the coolant.......................... 8-61
Axle boots ........................................... 8-69
Spark plug inspection ......................... 8-71
Air filter element cleaning ................... 8-77
Carburetor adjustment ........................ 8-85
Idle speed adjustment ........................ 8-87
Valve clearance adjustment ............... 8-89
Throttle lever adjustment .................... 8-89
Front brake pad check ........................ 8-91
Rear brake pad inspection.................. 8-91
Inspecting the brake fluid level ........... 8-93
Brake fluid replacement ...................... 8-97
Front brake lever free play.................. 8-99
Rear brake lever and pedal 
adjustment ...................................... 8-101
Adjusting the rear brake light 
switch ............................................. 8-105
Cable inspection and lubrication....... 8-107
8
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2-1
SAFETY INFORMATION
EBU00661
AN ATV IS NOT A TOY AND CAN BE HAZARD-OUS TO OPERATE.
 An ATV handles differently
from other vehicles including motorcycles and
cars. A collision or rollover can occur quickly, even
during routine maneuvers such as turning and
riding on hills or over obstacles, if you fail to take
proper precautions.
SEVERE INJURY OR DEATH can result if you do
not follow these instructions:
Read this manual and all labels carefully and
follow the operating procedures described.
Never operate an ATV without proper instruc-
tion.
Always follow the age recommendation:
– A child under 16 years old should never oper-
ate an ATV with engine size greater than 90cc.
Never allow a child under age 16 to operate an
ATV without adult supervision, and never allow
continued use of an ATV by a child if he or she
does not have the abilities to operate it safely.
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2-15
WARNING
Always turn off the engine when refueling.
Do not refuel right after the engine has
been running and is still very hot.
Do not spill gasoline on the engine or ex-
haust pipe/muffler when refueling. Never
refuel while smoking, or while in the vicin-
ity of sparks, open flames, or other sourc-
es of ignition such as the pilot lights of
water heaters and clothes dryers. Gaso-
line can catch fire and you could be
burned.
When transporting the machine in anoth-
er vehicle, be sure it is kept upright and
that the fuel cock is in the “OFF” position.
Otherwise, fuel may leak out of the carbu-
retor or fuel tank.
Gasoline is poisonous. If you should
swallow some gasoline or inhale a lot of
gasoline vapor, or get some gasoline in
your eyes, see your doctor immediately. If
gasoline spills on your skin, wash with
soap and water. If gasoline spills on your
clothing, change your clothes.
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3-1
EBU00032
DESCRIPTION AND MACHINE 
IDENTIFICATION1. Rear shock absorber spring 
preload adjusting ring
2. Storage compartment and tool 
kit
3. Air filter case
4. Front brake fluid reservoir
5. Front shock absorber spring 
preload adjusting ring
6. Rear brake fluid reservoir
7. Rear brake pedal
8. V-belt case drain plug
9. Radiator cap
10. Drive select lever
11. Fuel tank cap
12. Fuel cock
13. Fuses14. Battery
15. Engine oil dipstick
16. Recoil starter
17. Coolant reservoir
18. Drive select lever box check 
hose 
19. V-belt cooling duct check hose
20. Rear brake lever
21. Left handlebar switches
22. Horn
23. Speedometer unit
24. Main switch
25. Right handlebar switches
26. Throttle lever
27. Front brake lever
28. Auxiliary DC jack
29. Starter (choke)NOTE:The machine you have purchased may differ
slightly from those shown in the figures of this
manual.
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4-1 1. Main switch
1. Contacteur à clé
1. Interruptor principal
EBU00040
CONTROL FUNCTIONS
EBU00942
Main switch
Functions of the respective switch positions are as
follows: 
ON: 
The engine can be started only at this position and
the headlights and taillight come on when the light
switch is on. 
OFF: 
All electrical circuits are switched off. The key can
be removed in this position.
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4-7
EBU00860
Coolant temperature warning light “”
When the coolant temperature reaches a specified
level, this light comes on to warn that the coolant
temperature is too hot. If the light comes on during
operation, stop the engine as soon as it is safe to
do so and allow the engine to cool down for about
10 minutes.CAUTION:_ 
The engine may overheat if the ATV is
overloaded. If this happens, reduce the
load to specification.
After restarting, make sure that the light is
out. Continuous use while the light is on
may cause damage to the engine. 
_ 
1. Differential gear lock indicator light “DIFF. LOCK”
2. Low-range indicator light “L”
3. High-range indicator light “H”
4. Neutral indicator light “N”
5. Reverse indicator light “R”
6. Park indicator light “P”
7. Four-wheel-drive indicator “”/“”
8. Coolant temperature warning light “”
1. Témoin de blocage du différentiel “DIFF. LOCK” 
2. Témoin du rapport inférieur “L”
3. Témoin du rapport supérieur “H”
4. Témoin de point mort “N”
5. Témoin de marche arrière “R” 
6. Témoin de stationnement “P”
7. Indicateur 4x4 “”/“”
8. Témoin d’avertissement de la température du liquide de 
refroidissement “”
1. Luz indicadora de bloqueo del diferencial “DIFF.LOCK”
2. Luz indicadora de margen bajo “L”
3. Luz indicadora de margen alto “H”
4. Luz de control de punto muerto “N”
5. Luz indicadora de marcha atrás “R”
6. Luz indicadora de estacionamiento “P”
7. Indicador del modo de tracción en las cuatro ruedas “”/“”
8. Luz de aviso de la temperatura del refrigerante “”
DIFF.
LOCK
DIFF.
LOCK
DIFF.
LOCK
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4-17 1. Lights switch “//OFF”
2. Start switch “”
3. Engine stop switch “/”
4. Override switch “OVERRIDE”
5. Horn switch “”
1. Contacteur d’éclairage “//OFF”
2. Contacteur du démarreur “”
3. Coupe-circuit du moteur “/”
4. Contacteur de désactivation “OVERRIDE”
5. Contacteur de l’avertisseur “”
1. Interruptor de luces “//OFF”
2. Interruptor de arranque “”
3. Interruptor de paro del motor “/”
4. Interruptor de cancelación “OVERRIDE”
5. Interruptor de la bocina “”
EBU00053
Handlebar switches
EBU01204
Light switch “/ /OFF”
Set the switch to “” to turn on the low beam and
the taillight.
Set the switch to “” to turn on the high beam
and the taillight.
Set the switch to “OFF” to turn off all the lights.CAUTION:_ Do not use the headlights with the engine
turned off for more than thirty minutes. The
battery may discharge to the point that the
starter motor will not operate properly. If this
should happen, remove the battery and re-
charge it. _ 
EBU01205
Engine stop switch “/” 
Make sure that the engine stop switch is set to
“” before starting the engine. The engine stop
switch controls ignition and can be used at all
times to stop the engine, especially in an emer-
gency. The engine will not start or run when the
engine stop switch is set to “”.
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4-19 1. Lights switch “//OFF”
2. Start switch “”
3. Engine stop switch “/”
4. Override switch “OVERRIDE”
5. Horn switch “”
1. Contacteur d’éclairage “//OFF”
2. Contacteur du démarreur “”
3. Coupe-circuit du moteur “/”
4. Contacteur de désactivation “OVERRIDE”
5. Contacteur de l’avertisseur “”
1. Interruptor de luces “//OFF”
2. Interruptor de arranque “”
3. Interruptor de paro del motor “/”
4. Interruptor de cancelación “OVERRIDE”
5. Interruptor de la bocina “”
EBU00607
Start switch “”
The starter motor cranks the engine when this
switch is pushed.CAUTION:
See starting instructions prior to starting the
engine. (See page 6-3 for details.)
EBU00059
Horn switch “”
Press the switch to sound the horn.
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4-21 1. Override switch “OVERRIDE”
1. Contacteur de désactivation “OVERRIDE”
1. Interruptor de cancelación “OVERRIDE”
EBU13811
Override switch “OVERRIDE”
Top speed is normally limited when operating in
4WD-LOCK. If conditions require more engine
power when riding forward, push and hold this
switch to override the 4WD-LOCK speed limiting
function. (See page 4-31 for a detailed explanation
about the differential gear lock switch and its func-
tion.) Releasing the switch restores the speed lim-
iting function. 
While this switch is pushed, the segments of the
speedometer digits will appear as shown in the fig-
ure.NOTE:_ If the digits of the speedometer appear as shown
when the switch is NOT being pushed, this could
indicate a malfunction in the electrical system. In
this case, take the ATV to a Yamaha dealer at the
first opportunity. _
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