2008 YAMAHA GRIZZLY 660 maintenance

EBU17170
INTRODUCTION
EBU17290Congratulations on your purchase of the Yamaha YFM66FGX. This ATV represents the result of many
years of Yamaha experience in the production of fine sporting, touring, and pacesetting racing machines.
With the purchase of this Yamaha, you can now appreciate the high degree of craftsmanship and reliability
that have made Yamaha a leader in these fields.
This manual will provide you with a good basic understanding of the features and operation of this ATV.
This manual includes important safety information. It provides information about special tech-
niques and skills necessary to ride the ATV. It also includes basic maintenance and inspection proce-
dures. If you have any questions regarding the operation or maintenance of your ATV, please consult a
Yamaha dealer.
AN IMPORTANT SAFETY MESSAGE:
READ THIS MANUAL COMPLETELY BEFORE OPERATING YOUR ATV. MAKE SURE YOU UNDER-
STAND ALL INSTRUCTIONS.
PAY CLOSE ATTENTION TO THE WARNING AND CAUTION LABELS ON THE ATV.
THIS ATV, AND ANY OTHER ATV OVER 90 cc, SHOULD NOT BE RIDDEN BY ANYONE UNDER 16
YEARS OF AGE.
U23D60E0.book Page 1 Thursday, March 15, 2007 7:59 PM

OPERATION .................................................. 6-1
Starting a cold engine ................................ 6-1
Starting a warm engine .............................. 6-3
Operating the drive select lever and
driving in reverse ...................................... 6-3
Engine break-in .......................................... 6-5
Parking ....................................................... 6-6
Parking on a slope ..................................... 6-6
Accessories and loading ............................ 6-6
RIDING YOUR ATV ...................................... 7-1
GETTING TO KNOW YOUR ATV............... 7-2
RIDE WITH CARE AND
GOOD JUDGEMENT ................................ 7-2
BE CAREFUL WHERE YOU RIDE ............. 7-9
TURNING YOUR ATV .............................. 7-13
CLIMBING UPHILL ................................... 7-14
RIDING DOWNHILL.................................. 7-17
CROSSING A SLOPE............................... 7-18
CROSSING THROUGH
SHALLOW WATER................................. 7-19
RIDING OVER ROUGH TERRAIN ........... 7-22
SLIDING AND SKIDDING ......................... 7-22
WHAT TO DO IF... .................................... 7-23
WHAT TO DO... ........................................ 7-23PERIODIC MAINTENANCE AND
MINOR REPAIR .............................................8-1
Owner’s manual and tool kit .......................8-1
Periodic maintenance chart for
the emission control system .....................8-3
General maintenance and
lubrication chart ........................................8-5
Removing and installing panels ..................8-9
Checking the spark plug ...........................8-16
Engine oil and oil filter cartridge ................8-18
Final gear oil .............................................8-22
Differential gear oil ....................................8-24
Coolant .....................................................8-26
Cleaning the air filter element ...................8-30
Cleaning the spark arrester ......................8-34
V-belt cooling duct check hose .................8-35
V-belt case drain plug ...............................8-35
Adjusting the carburetor ............................8-36
Adjusting the engine idling speed .............8-36
Adjusting the throttle cable free play .........8-37
Valve clearance ........................................8-38
Adjusting the drive select lever
safety system cable ................................8-38
Checking the front and rear brake pads ...8-38
Checking the brake fluid level ...................8-39
Changing the brake fluid ...........................8-41
Checking the front brake lever free play ...8-41U23D60E0.book Page 2 Thursday, March 15, 2007 7:59 PM

1-2
1

Always inspect your ATV each time you use it to
make sure it is in safe operating condition. Al-
ways follow the inspection and maintenance
procedures and schedules described in this
manual.
Always keep both hands on the handlebars and
both feet on the footboards of the ATV during
operation.
Always go slowly and be extra careful when op-
erating on unfamiliar terrain. Always be alert to
changing terrain conditions when operating the
ATV.
Never operate on excessively rough, slippery or
loose terrain until you have learned and prac-
ticed the skills necessary to control the ATV on
such terrain. Always be especially cautious on
these kinds of terrain.
Always follow proper procedures for turning as
described in this manual. Practice turning at low
speeds before attempting to turn at faster
speeds and never turn at excessive speeds.
Never operate the ATV on hills too steep for the
ATV or for your abilities. Practice on smaller hills
before attempting larger hills.

Always follow proper procedures for climbing
hills as described in this manual. Check the ter-
rain carefully before you start up any hill. Never
climb hills with excessively slippery or loose sur-
faces. Shift your weight forward. Never open the
throttle suddenly. Never go over the top of a hill
at high speed.
Always follow proper procedures for going down
hills and for braking on hills as described in this
manual. Check the terrain carefully before you
start down any hill. Shift your weight backward.
Never go down a hill at high speed. Avoid going
down a hill at an angle that would cause the ve-
hicle to lean sharply to one side. Go straight
down the hill where possible.
Always follow proper procedures for crossing
the side of a hill as described in this manual.
Avoid hills with excessively slippery or loose sur-
faces. Shift your weight to the uphill side of the
ATV. Never attempt to turn the ATV around on
any hill until you have mastered the turning tech-
nique described in this manual on level ground.
Avoid crossing the side of a steep hill if possible.
Always use proper procedures if you stall or roll
backwards when climbing a hill. To avoid stall-
ing, use the proper gear range and maintain a
U23D60E0.book Page 2 Thursday, March 15, 2007 7:59 PM

5-1
5
EBU19200
PRE-OPERATION CHECKS
EBU19221Pre-operation check list Before operating this ATV, be sure to check the items listed in the following table.NOTE:The maintenance of some items in the table has to be performed by a Yamaha dealer. Refer to the periodicmaintenance charts on page 8-3 to determine which service should be performed by a Yamaha dealer.
ITEM ROUTINE PAGE
FuelCheck fuel level in fuel tank, and add recommended fuel if neces-
sary.
Check fuel line for leakage. Correct if necessary.4-15, 5-3
Engine oilCheck oil level in engine, and add recommended oil to specified lev-
el if necessary.
Check ATV for oil leakage. Correct if necessary.5-3, 8-18
Final gear oilCheck ATV for oil leakage. Correct if necessary. 5-3, 8-22
Differential gear oilCheck ATV for oil leakage. Correct if necessary. 5-3, 8-24
CoolantCheck coolant level in reservoir, and add recommended coolant to
specified level if necessary.
Check cooling system for leakage. Correct if necessary.5-3, 8-26
Front brakeCheck operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
Check brake pads for wear, and replace if necessary.
Check brake fluid level in reservoir, and add recommended brake
fluid to specified level if necessary.
Check hydraulic system for leakage. Correct if necessary.5-4, 8-38, 8-39, 8-41
U23D60E0.book Page 1 Thursday, March 15, 2007 7:59 PM

5-2
5
WARNING
EWB00480Always inspect your ATV each time you use it to make sure it is in safe operating condition.
Always follow the inspection and maintenance procedures and schedules described in the Owner’sManual. Failure to inspect increases the possibility of an accident or equipment damage.Rear brakeCheck operation. If soft or spongy, have Yamaha dealer bleed hy-
draulic system.
Check lever free play, and adjust if necessary.
Check brake pads for wear, and replace if necessary.
Check brake fluid level in reservoir, and add recommended brake
fluid to specified level if necessary.
Check hydraulic system for leakage. Correct if necessary.5-4, 8-38, 8-39, 8-42
Throttle leverMake sure that operation is smooth. Lubricate cable and lever hous-
ing if necessary.
Check cable free play, and adjust if necessary.5-5, 8-37
Control cablesMake sure that operation is smooth. Lubricate if necessary. 8-45
Wheels and tiresCheck wheel condition, and replace if damaged.
Check tire condition and tread depth. Replace if necessary.
Check air pressure. Correct if necessary.5-5, 5-6, 5-7
Brake pedal Make sure that operation is smooth. Lubricate pedal pivoting point if
necessary.8-46
Brake leversMake sure that operation is smooth. Lubricate lever pivoting points if
necessary.8-45
Axle bootsCheck for cracks or damage, and replace if necessary. 8-44
Chassis fastenersMake sure that all nuts, bolts and screws are properly tightened. 5-7
Instruments, lights and
switchesCheck operation, and correct if necessary. 5-7 ITEM ROUTINE PAGE
U23D60E0.book Page 2 Thursday, March 15, 2007 7:59 PM

8-1
8
EBU28780
PERIODIC MAINTENANCE AND MINOR REPAIR
EBU21670Safety is an obligation of the owner. Periodic in-
spection, adjustment and lubrication will keep your
ATV in the safest and best operating condition
possible. The most important points of inspection,
adjustment, and lubrication are explained on the
following pages.
The intervals given in the periodic maintenance
and lubrication chart should be considered as a
general guide under normal riding conditions.
However, DEPENDING ON THE WEATHER,
TERRAIN, GEOGRAPHICAL LOCATION, AND
INDIVIDUAL USE, THE MAINTENANCE INTER-
VALS MAY NEED TO BE SHORTENED.
WARNING
EWB01840Never service an engine while it is running.
Moving parts can catch clothing or parts of the
body, causing injury. Electrical components
can cause shocks or start fires. Turn off the en-
gine when performing maintenance unlessotherwise specified. Have a Yamaha dealer
perform the service if you are not familiar with
maintenance work.EBU27110Owner’s manual and tool kit Be sure to put this owner’s manual in the plastic
bag and to always carry it as well as the owner’s
tool kit and the low-pressure tire gauge in their re-
spective compartments under the seat.1. Owner’s manual
2. Owner’s tool kit
3. Low-pressure tire gauge
U23D60E0.book Page 1 Thursday, March 15, 2007 7:59 PM

8-2
8The service information included in this manual
and the tools provided in the owner’s tool kit are in-
tended to assist you in the performance of preven-
tive maintenance and minor repairs. However,
additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
NOTE:If you do not have the tools or experience required
for a particular job, have a Yamaha dealer performit for you.
WARNING
EWB01850Never modify this ATV through improper in-
stallation or use of accessories, as it may
cause changes in handling, which in some sit-
uations could lead to an accident. All parts and
accessories added to this ATV should be gen-
uine Yamaha or equivalent components de-
signed for use on this ATV and should be
installed and used according to instructions. If
you have questions, consult an authorizedYamaha ATV dealer.U23D60E0.book Page 2 Thursday, March 15, 2007 7:59 PM

8-3
8
EBU21742Periodic maintenance chart for the emission control system NOTE:
For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should be followed.
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,data and technical skills.NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
1*Fuel lineCheck fuel hoses for cracks or other damage, and
replace if necessary.√√√
2 Spark plugCheck condition and clean, regap, or replace if
necessary.√√√√√
3*ValvesCheck valve clearance and adjust if necessary.√ √√√
4*CarburetorCheck starter (choke) operation and correct if nec-
essary.
Check engine idling speed and adjust if neces-
sary.√√√√
5*Crankcase breather
systemCheck breather hose for cracks or other damage,
and replace if necessary.√√√
U23D60E0.book Page 3 Thursday, March 15, 2007 7:59 PM