2009 YAMAHA YFM90R engine

9
Make sure that operation is smooth, and check cable free play.Lubricate cable and lever housing if necessary.
Control cablesMake sure that operation is smooth. Lubricate if necessary. 8-27
Wheels and tiresCheck wheel condition, and replace if damaged.Check tire condition and tread depth. Replace if necessary.Check air pressure. Correct if necessary. 5-4, 5-5, 5-6
Brake leversMake sure that operation is smooth. Lubricate lever pivoting points
if necessary. 8-27
Chassis fastenersMake sure that all nuts, bolts and screws are properly tightened. 5-7
Instruments and switchesCheck operation, and correct if necessary. 5-7
2
5-2
9
Throttle lever 5-4, 8-21
5
PAGE
ROUTINE
METIT
Fuel
Check fuel line for leakage. Correct if necessary . 4-8, 5-3Check A TV for oil leakage. Correct if necessary .5-3, 8-11
Final transmission oil
5-3, 8-14
Check ATV for oil leakage. Correct if necessary.
Front brake
Check operation, and correct if necessary.Lubricate cable if necessary .Check lever free play , and adjust if necessary. 5-3, 8-22, 8-23
Engine oil
Check fuel level in fuel tank, and add recommended fuel if neces-
sary.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. Check operation. If soft or spongy, have Yamaha dealer bleed
hydraulic system.
Rear brake 5-3, 8-25, 8-26
Check oil level in engine, and add recommended oil to specified
level if necessary.

5-3
FuelMake sure that there is sufficient fuel in the tank.
(See page 4-8.)
Engine oilMake sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-11.)
Final transmission oilMake sure that the final transmission oil is at the
specified level. Add oil as necessary.
(See page 8-14.)Front and rear brakesRecommended brake fluid:
DOT4
3
Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joint or brake fluid reservoir. Apply the brake
firmly for one minute. If there is any leakage, have a
Yamaha dealer check the brake system.Brake leversCheck for correct free play in the brake levers. If
the free play is incorrect, adjust it. (See pages
8-23 and 8-26.)Check operation of the levers. They should
move smoothly and there should be a firm feel-
ATV checked by a Yamaha dealer.
6
Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-25.)
15
WARNING
Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is overfilled,
fuel could spill out due to heat from the en-
gine 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 securely.
ing when the brakes are applied. If not, have the

6-1

OPERATION
6
N O T I C E
See the “Engine break-in” section on page 6-4prior to operating the engine for the first time.1. Set the parking brake.
2. Turn the fuel cock to “ON”.
3. Turn the main switch to “ON” and the engine stop switch to “RUN”.
Read the Owner’s Manual carefully before riding
the ATV.
WARNING
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. If there is a control or func-
tion you do not understand, ask your Yamahadealer. Starting a cold engine
WARNING
Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or do
not work smoothly, you could be unable to
control the ATV, which could lead to an acci-dent or collision.

6-2
Ambient temp./choke position
5. Completely close the throttle lever and start
the engine by pushing the start switch.TIPIf 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 short
as possible to preserve battery energy. Do not1. Fully open “ON”
2. Half open (warming up position)
3. Closed “OFF”
4. Choke
0°
30° 10°
20° 30°
50° 70° 90° °F
°C
1
3
TIPThis model is equipped with an ignition circuit cut-
off system. The engine can be started only when
the rear brake lever is applied.4. Use the choke in reference to the figure:
Position (1):Cold engine start with ambient temperature be-
low 30 °C (90 °F).
Position (2):Warming up position.
Position (3):Cold engine start with ambient temperature
above 25 °C (80 °F).
66
1 3
2 4

6-3
6
crank the engine more than 10 seconds on eachattempt.6. If the engine is started with the choke in posi- tion (1), the choke should be returned to posi-
tion (2) to warm up the engine. If the engine is
started with the choke in position (2), keep the
choke in this position to warm up the engine.
N O T I C E
For maximum engine life, always warm the en-
gine up before starting off. Never acceleratehard when the engine is cold!
7. Continue warming up the engine until it idles smoothly, then return the choke to position (3)
before riding.TIPThe engine is warm when it responds normally tothe throttle with the choke turned off. Starting a warm engine Follow the same procedure as for starting a cold
engine, with the exception that the choke is not re-
quired when the engine is warm. Instead, start the
engine with the throttle slightly open.
To start out and accelerate1. Squeeze the front brake lever to release the parking brake.
2. Gradually open the throttle while slowly re- leasing the rear brake lever. To decelerate
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.
WARNING
Opening the throttle abruptly or releasing the
clutch lever too quickly could make the ATV
wheelie, which would increase the chance ofan accident, including an overturn.

Engine break-in 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
N O T I C E Do not tow the ATV for long distances. The
transmission is properly lubricated only when
the engine is running. Inadequate lubrication
may damage the transmission.
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.
N O T I C E
If any engine trouble should occur during the
engine break-in period, immediately have a ParkingWhen parking the ATV, stop the engine, shift the
drive select lever into the drive position, apply the
parking brake, and then turn the fuel cock to “OFF”. Yamaha dealer check the ATV. 320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.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.
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.
6-4
6

6-5
Parking on a slope1. Bring the ATV to a stop by applying the brakesin the drive position.
2. Stop the engine.
3. Apply the parking brake.
1. Parking brake lock button
1. Locked position
6
1
1
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 ATV transversely across the
incline, stop the engine, apply the parking
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 sosteep you could not walk up them easily.

7-3
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 12 years
of age.
7
WARNING
Never operate this ATV without proper instruc-
tion. Beginning and inexperienced operators
should regularly practice the skills and the op-
erating techniques described in this Owner’s
Manual. The risk of an accident is greatly in-
creased if the operator does not know how to
operate the ATV properly in different situationsand on different types of terrain.
WARNING
A child under 12 should never operate an ATV
with engine size greater than 70 cc. Use by chil-
dren of ATVs that are not recommended for
their age can lead to severe injury or death ofthe child.