engine YAMAHA GRIZZLY 660 2003 Owner's Guide

6-17
EBU00210
Engine break-in
There is never a more important period in the life of
your machine than the period between zero and
20 hours.
For this reason, we ask that you carefully read the
following material. Because the engine is brand
new, you must not put an excessive load on it for
the first several hours of running. During the first
20 hours, the various parts in the engine wear and
polish themselves to the correct operating clear-
ances.
During this period, prolonged full throttle operation
or any condition which might result in excessive
engine heating must be avoided. However, mo-
mentary (2 ~ 3 seconds maximum) full throttle op-
eration under load does not harm the engine.
Each full throttle acceleration sequence should be
followed with a substantial rest period for the en-
gine by cruising at lower r/min so the engine can
rid itself of the temporary build up of heat. If any
abnormality is noticed during this period, consult a
Yamaha dealer.
U5KM60.book Page 17 Thursday, June 21, 2001 2:40 PM

6-19
1. 0 ~ 10 hours:
Avoid continuous operation above half throt-
tle. Allow a cooling off period of five to ten
minutes after every hour of operation. Vary
the speed of the machine from time to time.
Do not operate it at one set throttle position.
2. 10 ~ 20 hours:
Avoid prolonged operation above 3/4 throttle.
Rev the machine freely but do not use full
throttle at any time.
3. After break-in:
Avoid prolonged full throttle operation. Vary
speeds occasionally.
EBU00612
Parking
When parking, stop the engine and shift the drive
select lever into the park position, then turn the fuel
cock to the “OFF” position.
U5KM60.book Page 19 Thursday, June 21, 2001 2:40 PM

6-21
EBU00676
Parking on a slope
WARNING
Avoid parking on hills or other inclines. Park-
ing on a hill or other incline could cause the
ATV to roll out of control, increasing the
chance of an accident. If you must park on an
incline, place the machine transversely across
the incline, apply the parking brake, and block
the front and rear wheels with rocks or other
objects. Do not park the ATV at all on hills that
are so steep you could not walk up them easi-
ly.1. Bring the machine to a stop by applying the
brakes.
2. Stop the engine.
3. With the rear brake applied, shift the drive
select lever to the park position.
U5KM60.book Page 21 Thursday, June 21, 2001 2:40 PM

7-7
Riding your ATV requires skills acquired
through practice over a period of time.
Take the time to learn the basic techniques well
before attempting more difficult maneuvers.
Not recommended for children under 16 years
of age.
WARNING
_ A child under 16 should never operate an ATV
with engine size greater than 90cc. Use by chil-
dren of ATVs that are not recommended for
their age can lead to severe injury or death of
the child. _
U5KM60.book Page 7 Thursday, June 21, 2001 2:40 PM

7-17 1. Locknut 2. Adjusting bolt
1. Contre-écrou 2. Boulon de réglage
1. Contratuerca 2. Perno de ajuste
Speed limiter
For riders less experienced with this model, this
model is equipped with a speed limiter in the throt-
tle lever housing. The speed limiter keeps the
throttle from fully opening, even when the throttle
lever is pushed to the maximum. Screwing in the
adjuster limits the maximum engine power avail-
able and decreases the maximum speed of the
ATV. Turning the screw in decreases top speed
and turning it out increases top speed.
Loading and accessories
Use extra caution when riding the ATV with addi-
tional loads, such as accessories or cargo. The
ATV’s handling may be adversely affected. Re-
duce your speed when adding additional loads.
U5KM60.book Page 17 Thursday, June 21, 2001 2:40 PM

7-35
Select a large, flat area off-road to become familiar
with your ATV. Make sure that this area is free of
obstacles and other riders. You should practice
control of the throttle, brakes, shifting procedures,
and turning techniques in this area before trying
more difficult terrain. Always avoid riding on paved
surfaces: the ATV is designed for off-road use
only, and handling maneuvers are more difficult to
perform on pavement.
Shift to the parking position “P” and follow the in-
struction on page 6-1 to start the engine. Once it
has warmed up you are ready to begin riding your
ATV. Remember that the engine and exhaust pipe
will be hot when riding and afterwards; do not al-
low skin or clothing to come in contact with these
components.
U5KM60.book Page 35 Thursday, June 21, 2001 2:40 PM

7-37
With the engine idling, shift the drive select lever to
the low position “L” or the high position “H”. Apply
the throttle slowly and smoothly. The centrifugal
clutch will engage and you will start to accelerate.
If the throttle is applied too abruptly, the front
wheels may lift off the ground resulting in a loss of
directional control. Avoid higher speeds until you
are thoroughly familiar with the operation of your
ATV.
When slowing down or stopping, release the throt-
tle and apply the brakes smoothly and evenly. Im-
proper use of the brakes can cause the tires to
lose traction, reducing control and increasing the
possibility of an accident.CAUTION:_ Do not shift from drive position low “L” to high
“H” or vice versa without coming to a com-
plete stop. Damage to the engine or drive train
may occur. _
U5KM60.book Page 37 Thursday, June 21, 2001 2:40 PM

7-55
RIDING DOWNHILL
When riding your ATV downhill, shift your weight
as far to the rear and uphill side of the ATV as pos-
sible. Move back on the seat and sit with your
arms straight. Engine compression will do most of
the braking for you. For maximum engine com-
pression braking effect, select low range “L” and
change to 4WD or 4WD-LOCK before beginning
to descend the hill. Improper braking may cause a
loss of traction. Use caution while descending a hill
with loose or slippery surfaces. Braking ability and
traction may be adversely affected by these sur-
faces. Improper braking may also cause a loss of
traction.
When this ATV is in 4WD or 4WD-LOCK, all
wheels (front and rear) are interconnected by the
drive train. This means that applying either the
front brake or the rear brake will brake all wheels.
When descending hills, using either brake lever or
the brake pedal will brake the wheels on the down-
hill side. Avoid sudden application of either the
front or rear brake because the wheels on the up-
hill side could come off the ground. Apply both the
front and rear brakes gradually.
U5KM60.book Page 55 Thursday, June 21, 2001 2:40 PM

8-1
EBU00516
PERIODIC MAINTENANCE AND
ADJUSTMENTPeriodic inspection, adjustment and lubrication will
keep your machine in the safest and most efficient
condition possible. Safety is an obligation of the
machine owner. The most important points of ma-
chine inspection, adjustment and lubrication are
explained on the following pages.
WARNING
Never 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 can start fires. Turn off
the engine when performing maintenance un-
less otherwise specified. Have a Yamaha deal-
er perform service if you are not familiar with
machine service.
U5KM60.book Page 1 Thursday, June 21, 2001 2:40 PM

8-7
EBU00262
PERIODIC MAINTENANCE/LUBRICATION
ITEM ROUTINEWhichever
comes firstINITIAL EVERY
km 320 1,200 2,400 2,400 4,800
hours 20 75 150 150 300
Valves*•Check valve clearance.
•Adjust if necessary.
Cooling system•Check coolant leakage.
•Repair if necessary.
•Replace coolant every 24 months.Spark plug•Check condition.
•Adjust gap and clean.
•Replace if necessary.Air filter•Clean.
•Replace if necessary.Every 20~40 hours
(More often in wet or dusty areas.)
Carburetor*•Check and adjust idle speed/starter operation.
•Adjust if necessary.Crankcase breather
system*•Check breather hose for cracks or damage.
•Replace if necessary.Exhaust system*•Check for leakage.
•Retighten if necessary.
•Replace gasket(s) if necessary.Fuel line*•Check fuel hose for cracks or damage.
•Replace if necessary.Engine oil
•Replace (Warm engine before draining).Engine oil filter cartridge
•Replace.Final gear oil
•Check oil level/oil leakage.
•Replace.Differential gear oil
Front brake*•Check operation/fluid leakage/see NOTE page 8-8.
•Correct if necessary.Rear brake*•Check operation/fluid leakage/see NOTE page 8-8.
•Correct if necessary.V-belt*•Check operation.
•Check for cracks or damage.U5KM60.book Page 7 Thursday, June 21, 2001 2:40 PM