2010 YAMAHA GRIZZLY 125 engine

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EBU19880
OPERATION
EBU19901
Read the Owner’s Manual carefully before riding
the ATV. If there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING

EWB00631
Read the Owner’s Manual carefully to become
familiar with all controls in order to help pre-
vent any loss of control, which could cause an
accident or injury.
EBU29720
Starting a cold engine
NOTICE

ECB00150
See the “Engine break-in” section on page 6-4
prior to operating the engine for the first time.
1. Set the parking brake.
2. Turn the fuel cock to “ON”.
3. Turn the key to “ON” and the engine stop
switch to “”.
4. Shift the drive select lever into the neutral po-sition. The neutral indicator light should come
on. If the indicator light does not come on,
have a Yamaha dealer check the electrical cir-
cuit.
TIP

The engine can be started only when the drive se-
lect lever is in the neutral position.
5. Use the starter (choke) in reference to the fig-
ure:
Position (1):
Cold engine start with ambient temperature
below 5 °C (40 °F).
Position (2):
Cold engine start with ambient temperature
between 0 °C (30 °F) and 30 °C (90 °F).
Position (3):
Cold engine start with ambient temperature
above 25 °C (80 °F).

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Ambient temp./starter (choke) position

6. Completely close the throttle lever and
start the engine by pushing the start switch.
NOTICE:
For maximum engine life, nev-
er accelerate hard when the engine is
cold!
[ECB00162]

TIP

If the engine fails to start, release the start switch,
then push it again. Pause a few seconds before
the next attempt. Each cranking should be as shortas possible to preserve battery energy. Do not
crank the engine more than 10 seconds on each
attempt.
7. If the engine is started with the starter (choke)
in position (1), the starter (choke) should be
returned to position (2) to warm up the engine.
If the engine is started with the starter (choke)
in position (2), keep the starter (choke) in this
position to warm up the engine.
8. Continue warming up the engine until it idles
smoothly, then return the starter (choke) to
position (3) before riding.
TIP

The engine is warm when it responds normally to
the throttle with the starter (choke) turned off.
EBU20291
Starting a warm engine
Follow the same procedure as for starting a cold
engine, with the exception that the starter (choke)
is not required when the engine is warm. Instead,
start the engine with the throttle slightly open.
1. Fully open
2. Half open
3. Closed
4. Starter (choke)
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go slowly.
1. Bring the ATV to a complete stop.
2. Apply the parking brake.
3. Shift from neutral to reverse and vice versa by
moving the drive select lever along the shift
guide.
TIP

When in reverse, the reverse indicator light should
come on. If the indicator light does not come on,
have a Yamaha dealer check the electrical circuit.
4. Check behind for people or obstacles, and
then release the parking brake.
5. Open the throttle lever gradually and continue
to watch to the rear while backing.
TIP

If the drive select lever is shifted into reverse while
the engine is running, the engine will stop unless
the rear brake lever or parking brake is applied.
EBU20682
Engine break-in
TIP


For ATVs equipped with an odometer or an hourmeter, follow the figures given in km (mi) or the
figures given in hours.

For ATVs not equipped with an odometer or
hour meter, follow the figures given in hours.
There is never a more important period in the life of
your engine than the first 320 km (200 mi) or 20
hours of riding. For this reason, you should read
the following material carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 320 km (200 mi) or 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 that might result in en-
gine overheating must be avoided.
0–160 km (0–100 mi) or 0–10 hours
Avoid prolonged operation above 1/2 throttle. Vary
the speed of the ATV regularly. Do not operate it at
one set throttle position.
160–320 km (100–200 mi) or 10–20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine freely, but do not use full throttle at any
time.

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320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICE

ECB00220
If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV.
EBU20700
Parking
When parking the ATV, stop the engine, shift the
drive select lever into the forward position, apply
the parking brake, and then turn the fuel cock to
“OFF”.
EBU20740
Parking on a slope WARNING
EWB00830
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 ATV transversely across the
incline, shift the drive select lever to the for-
ward position, stop the engine, apply the park-
ing brake, and then 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 easily.
1. Bring the ATV to a stop by applying the brakes
in the forward position.
2. Stop the engine.
3. With the rear brake applied, apply the parking
brake.
1. Locked position
1

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handling and performance characteristics. Take
the time to learn the basic techniques well before
attempting more difficult maneuvers. Become fa-
miliar with this ATV at slow speeds first, even if you
are an experienced operator.
Not recommended for children under 16 years
of age.
WARNING

EWB01390
A child under 16 should never operate an ATV
with engine size greater than 90 cc. Use by chil-
dren of ATVs that are not recommended for
their age can lead to severe injury or death of
the child.This ATV is designed to carry the operator
and cargo only – passengers prohibited.
The long seat is to allow the operator to shift posi-
tion as needed during operation. It is not for carry-
ing passengers.
WARNING! Never carry a
passenger. Carrying a passenger on this ATV
greatly reduces your ability to balance and
control this ATV. You could have an accident,
resulting in severe injury or death to you and/
or your passenger.
[EWB01401]

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iter. The speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed to
the maximum. Turning in the adjusting screw limits
the maximum engine power available and de-
creases the maximum speed of the ATV. Turning
in the adjusting screw decreases top speed, and
turning it out increases top speed. (See page 4-3.)
Loading and accessories
Take extra precautions when driving with a load or
trailer. Follow these instructions and always use
common sense and good judgment when carrying
cargo or towing a trailer.
WARNING

EWB01461
Improper loading or towing can increase the
risk of loss of control, an overturn, or other ac-
cident. To reduce the risk of an accident:

Do not exceed the maximum loading limits
for the vehicle (see box in this section or ve-
hicle labeling).

Keep weight on racks centered side to side,
and as low as possible. Be sure cargo is se-
cured – a loose load could change handling
unexpectedly.

Make sure the load does not interfere with
your control or ability to see where you are
going.

Tie down cargo in the trailer securely. Make
sure cargo in the trailer cannot move around.
A shifting load can cause an accident.

Reduce speed and allow more room to stop.
A heavier vehicle takes longer to stop.

Avoid hills and rough terrain. Choose terrain
carefully. Use extreme caution when towing
or carrying a load on inclines.
1. Adjusting screw
2. Locknut
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Modifications and accessories
Never modify this ATV through improper installa-
tion or use of accessories or other modification. All
parts and accessories added to this ATV should be
genuine 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 authorized ATV dealer.
WARNING! Operating this ATV with improper
modifications may cause changes in handling
which in some situations could lead to an acci-
dent.
[EWB01491]
Exhaust system
WARNING

EWB01501

Dry grass or brush or other combustible ma-
terial accumulated around the engine area
could catch fire. Do not operate, idle, or park
the ATV in dry grass or other dry ground cov-
er. Keep the engine area free of dry grass,
brush, or other combustible material.

Someone touching the exhaust system dur-
ing or after operation could be burned. Do
not touch the hot exhaust system. Do not
park the ATV in a place where others might
be likely to touch it.
The muffler and other engine parts become ex-
tremely hot during operation and remain hot after
the engine has stopped. To reduce the risk of fire
during operation or after leaving the ATV, do not let
brush, grass and other materials collect under the
vehicle, near the muffler or exhaust pipe, or next to
other hot parts. Check under the vehicle after op-
erating in areas where combustible materials may
have collected. Do not idle or park the vehicle in
long dry grass or other dry ground cover.
To prevent burns, avoid touching the exhaust sys-
tem. Park the ATV in a place where pedestrians or

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Select a large, flat, unpaved area to become famil-
iar 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.
Set the parking brake and follow the instruction on
page 6-1 to start the engine. Once it has warmed
up you are ready to begin riding your ATV. With the
engine idling, return the starter knob to the closed
position and shift the drive select lever into the for-
ward position, then release the parking brake. Ap-
ply 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 ina 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 possi-
bility of an accident.
TURNING YOUR ATV
WARNING

EWB01771
Always follow proper procedures for turning
as described in this Owner’s Manual. Practice
turning at low speeds before attempting to turn
at faster speeds. Do not turn at speeds too fast
for your skills or the conditions. ATV could go
out of control, causing a collision or overturn.
To achieve maximum traction on unpaved surfac-
es, the two rear wheels turn together at the same
speed. Therefore, unless the wheel on the inside
of the turn is allowed to slip or lose some traction,
the ATV will resist turning. A special turning tech-
nique must be used to allow the ATV to make turns
quickly and easily. It is essential that this skill be
learned first at low speed.