8-36
8
EBU23940Adjusting the carburetor The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the peri-
odic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. Therefore,
most carburetor adjustments should be left to a
Yamaha dealer, who has the necessary profes- sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
tenance.NOTICEECB00480The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine.EBU24010Adjusting the engine idling speed The engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
tion chart.
TIPA diagnostic tachometer is needed to make this
adjustment.1. Start the engine and warm it up.TIPThe engine is warm when it quickly responds to the
throttle.2. Remove panel C. (See page 8-10.)
3. Attach the tachometer to the spark plug lead.
4. Check the engine idling speed and, if neces- sary, adjust it to specification by turning the
throttle stop screw at the carburetor. To in-
crease the engine idling speed, turn the throt-
tle stop screw in direction (a), and to decrease
it, turn the screw in direction (b).
U2LC60E0.book Page 36 Friday, March 8, 2013 1:18 PM
8-65
8
EBU25785Troubleshooting charts Starting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
The engine does not start.
Check the ignition.
Operate the electric starter.4. Compression
There is compression.
There is no compression.
The engine does not start. Have a Yamaha dealer check the ATV.Have a Yamaha dealer check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug. Have a Yamaha dealer check the ATV.
The engine does not start.
Check the compression.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
U2LC60E0.book Page 65 Friday, March 8, 2013 1:18 PM
9-1
9
EBU25860
CLEANING AND STORAGE
EBU25881Cleaning Frequent, thorough cleaning of your ATV will not
only enhance its appearance but will improve its
general performance and extend the useful life of
many components.1. Before cleaning the ATV: a. Block off the end of the exhaust pipe toprevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps are properly installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply de-
greaser to the wheel axles.
3. Rinse the dirt and degreaser off with a garden hose. Use only enough pressure to do the job.
WARNING! Wet brakes may have reduced stopping ability, increasing the chance of
an accident. Test the brakes after washing.
Apply the brakes several times at slow
speeds to let friction dry out the linings.
[EWB02311]
NOTICE: Excessive water pressure
may cause water seepage and deteriora- tion of wheel bearings, brakes, transmis-
sion seals and electrical devices. Many
expensive repair bills have resulted from
improper high-pressure detergent applica-
tions such as those available in coin-oper-
ated car washers.
[ECB00711]
4. Once most of the dirt has been hosed off,
wash all surfaces with warm water and mild,
detergent-type soap. An old toothbrush or bot-
tle brush is handy for hard-to-reach places.
5. Rinse the ATV off immediately with clean wa- ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
7. Automotive type wax may be applied to all painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
U2LC60E0.book Page 1 Friday, March 8, 2013 1:18 PM
9-2
9
EBU25933Storage Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover. NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00721]
Long-term
Before storing your ATV for several months: 1. Follow all the instructions in the “Cleaning” section of this chapter.
2. Turn the fuel cock lever to “OFF”.
3. Drain the carburetor float chamber by loosen- ing the drain bolt; this will prevent fuel deposits
from building up. Pour the drained fuel into the
fuel tank.
4. Fill up the fuel tank and add fuel stabilizer (if available) to prevent the fuel from deteriorat-
ing. 5. Perform the following steps to protect the cyl-
inder, piston rings, etc. from corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the starter. (This will coat the cylinder wall with
oil.)
e. Remove the spark plug cap from the spark plug, and then install the spark plug and
the spark plug cap.
6. Lubricate all control cables and the pivoting points of all levers and pedals.
7. Check and, if necessary, correct the tire air pressure, and then block up the ATV so that
all of its wheels are off the ground. Alternative-
Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1
oz of stabilizer to each gallon of fuel)U2LC60E0.book Page 2 Friday, March 8, 2013 1:18 PM
10-3
10
Spark plug (s):Manufacturer/model:NGK/DR8EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:Wet, centrifugal automaticTransmission:Primary reduction system:V-belt
Secondary reduction system: Shaft drive
Secondary reduction ratio:
39/24 × 24/18 × 33/9 (7.944)
Transmission type: V-belt automatic
Operation: Left hand operation
Reverse gear:
29/17 (1.706)
Low range: 45/16 (2.813)
High range: 38/23 (1.652)Chassis:Frame type:Steel tube frame
Caster angle: 2.5 ° Trail:
8.5 mm (0.33 in)
Front tire:Type:
Tubeless
Size: AT25 x 8-12
Manufacturer/model: YFM450DE CHENG SHIN/C-828 (AUS)(NZL)
YFM450DE MAXXIS/MU13 (EUR)(FRA)(GBR)
YFM450PE CHENG SHIN/C-828 (AUS)(NZL)
YFM450PE MAXXIS/MU13 (EUR)(FRA)(GBR)
YFM450PHE MAXXIS/MU13Rear tire:Type:
Tubeless
Size: AT25 x 10-12
Manufacturer/model: YFM450DE CHENG SHIN/C-828 (AUS)(NZL)
YFM450DE MAXXIS/MU14 (EUR)(FRA)(GBR)
YFM450PE CHENG SHIN/C-828 (AUS)(NZL)
YFM450PE MAXXIS/MU14 (EUR)(FRA)(GBR)
YFM450PHE MAXXIS/MU14Loading:Maximum loading limit:
210.0 kg (463 lb)
(Total weight of rider, cargo, accessories, and tongue)
U2LC60E0.book Page 3 Friday, March 8, 2013 1:18 PM
Horn switch .................................................................... 4-7IIdentification numbers .................................................. 11-1
Indicator lights and warning lights .................................. 4-2
Instruments, lights and switches .................................... 5-7LLabel locations ............................................................... 1-1
Light switch .................................................................... 4-7
Low-range indicator light ................................................ 4-2MMain switch .................................................................... 4-1
Maintenance and lubrication chart ................................. 8-5
Maintenance chart, emission control system ................. 8-3
Model label ................................................................... 11-1
Multi-function display ..................................................... 4-5NNeutral indicator light ..................................................... 4-2OOn-Command differential gear lock switch .................... 4-9
On-Command four-wheel-drive switch ........................... 4-8
Override switch .............................................................. 4-7
Owner’s manual and tool kit ........................................... 8-2PPanels, removing and installing ................................... 8-10
Park indicator light ......................................................... 4-3
Parking ........................................................................... 6-5
Parking on a slope ......................................................... 6-6
Part locations ................................................................. 3-1RRear brake, adjusting the lever, pedal free play and pedal height ............................................................... 8-41
Rear knuckle pivots, lubricating ................................... 8-52 Reverse indicator light ................................................... 4-3
Riding your ATV ............................................................. 7-1
SSafety information .......................................................... 2-1
Seat ............................................................................. 4-18
Shock absorber assemblies, adjusting the front and
rear ............................................................................ 4-22
Spark arrester, cleaning ............................................... 8-33
Spark plug, checking ................................................... 8-14
Specifications ............................................................... 10-1
Speed limiter ................................................................ 4-12
Stabilizer bushes, checking ......................................... 8-51
Starter (choke) ............................................................. 4-18
Start switch .................................................................... 4-7
Steering shaft, lubricating ............................................ 8-52
Storage .......................................................................... 9-2
Storage compartments ................................................ 4-19TTail/brake light bulb, replacing ..................................... 8-60
Throttle lever ......................................................... 4-12, 5-4
Throttle lever free play, adjusting ................................. 8-37
Tires ............................................................................... 5-4
Troubleshooting ........................................................... 8-64
Troubleshooting charts ................................................ 8-65VValve clearance ........................................................... 8-38
V-belt case drain plug .................................................. 8-35
V-belt cooling duct check hose .................................... 8-35
Vehicle identification number ....................................... 11-1WWheel hub bearings, checking ..................................... 8-50
Wheel, installing ........................................................... 8-62
U2LC60E0.book Page 2 Friday, March 8, 2013 1:18 PM