2008 YAMAHA YFM250R engine

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the drive chain with steam cleaners, high-pres-
sure washers or inappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant.
CAUTION:

ECB00580
Do not use engine oil or any other lubricants
for the drive chain, as they may contain sub-
stances that could damage the O-rings.
EBU24900
Checking and lubricating the cables
The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING

EWB02130
Inspect cables frequently and replace if dam-aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could re-
strict the operation of controls and lead to an
accident or injury.
EBU24921
Checking and lubricating the brake and
clutch levers
The operation of the brake and clutch levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Recommended lubricant:
Engine oil
Recommended lubricants:
Brake lever:
Silicone grease
Clutch lever:
Lithium-soap-based grease (all-purpose
grease)

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EBU25751
Troubleshooting chart
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
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.
Have a Yamaha dealer
check the ATV.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.

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EBU25860
CLEANING AND STORAGE
EBU25900
Cleaning
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 to
prevent 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 chain, sprockets or wheel ax-
les.
3. Rinse the dirt and degreaser off with a garden
hose. Use only enough pressure to do the job.
CAUTION:

ECB00710
Excessive water pressure may cause water
seepage and deterioration of wheel bearings,
brakes, transmission seals and electrical de-
vices. Many expensive repair bills have result-ed from improper high-pressure detergent
applications such as those available in coin-
operated car washers.
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. Dry the chain and lubricate it to prevent it from
rusting.
7. Clean the seat with a vinyl upholstery cleaner
to keep the cover pliable and glossy.
8. 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.WARNING

EWB02310
Wet brakes may have reduced stopping ability,

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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.
EBU25932
Storage
Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover.
CAUTION:

ECB00720

Storing the ATV in a poorly ventilated 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 ammo-
nia) and areas where strong chemicals are
stored.
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 Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1 oz
of stabilizer to each gallon of fuel)

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EBU25960
SPECIFICATIONS
EBU2597A
Dimensions:
Overall length:
1625 mm (64.0 in)
Overall width:
1070 mm (42.1 in)
Overall height:
1040 mm (40.9 in)
Seat height:
730 mm (28.7 in)
Wheelbase:
1110 mm (43.7 in)
Ground clearance:
100 mm (3.9 in)
Minimum turning radius:
2900 mm (114 in)
Weight:
With oil and fuel:
150.0 kg (331 lb)
Engine:
Engine type:
Air cooled 4-stroke, SOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
249.0 cm
3

Bore
×
stroke:
74.0
×
58.0 mm (2.91
×
2.28 in)
Compression ratio:
9.50 :1
Starting system:
Electric starter
Lubrication system:
Wet sump

Engine oil:
Type:
SAE5W30 or SAE10W30 or SAE10W40 or SAE15W40
or SAE20W40 or SAE20W50
Recommended engine oil grade:
API service SG type or higher, JASO standard MA
-20˚-10˚0˚
10˚20˚30˚40˚50˚C
10W/30
15W/4020W/4020W/50
10W/40
5W/30

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Engine oil quantity:
Without oil filter element replacement:
1.25 L (1.32 US qt) (1.10 Imp.qt)
With oil filter element replacement:
1.35 L (1.43 US qt) (1.19 Imp.qt)
Air filter:
Air filter element:
Wet element
Fuel:
Recommended fuel:
Regular unleaded gasoline only (EUR)
Unleaded gasoline only (AUS)(NZL)
Fuel tank capacity:
9.0 L (2.38 US gal) (1.98 Imp.gal)
Fuel reserve amount:
1.0 L (0.26 US gal) (0.22 Imp.gal)
Carburetor:
Manufacturer:
MIKUNI
Type x quantity:
BSR29 x 1
Spark plug (s):
Manufacturer/model:
NGK/DR7EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Clutch:
Clutch type:
Wet, multiple-disc
Operation:
Left hand operation
Transmission:
Primary reduction system:
Spur gear
Primary reduction ratio:
76/22 (3.455)
Secondary reduction system:
Chain drive
Secondary reduction ratio:
38/14 (2.714)
Transmission type:
Constant mesh 5-speed
Operation:
Left foot operation
Gear ratio:
1st:
37/13 (2.846)
2nd:
33/18 (1.833)
3rd:
29/21 (1.381)
4th:
27/24 (1.125)
5th:
28/29 (0.966)
Chassis:
Frame type:
Steel tube frame
Caster angle:
6.0 °
Trail:
23.0 mm (0.91 in)

INDEX
A
Accessories and loading ................................................ 6-6
Air filter element, cleaning ............................................ 8-14
B
Battery .......................................................................... 8-36
Brake and clutch levers, checking and lubricating ....... 8-33
Brake and shift pedals, checking and lubricating ......... 8-34
Brake fluid, changing.................................................... 8-25
Brake fluid level, checking............................................ 8-23
Brake lever ..................................................................... 4-5
Brake lever free play, checking the front ...................... 8-26
Brake light switches ..................................................... 8-29
Brake pads, checking the front and rear ...................... 8-22
Brake pedal .................................................................... 4-5
Brake pedal position, checking .................................... 8-26
Brakes, front and rear .................................................... 5-3
C
Cables, checking and lubricating ................................. 8-33
Carburetor, adjusting.................................................... 8-19
Chassis fasteners........................................................... 5-7
Cleaning ......................................................................... 9-1
Clutch lever .................................................................... 4-4
Clutch lever free play, adjusting ................................... 8-29
D
Drive chain ..................................................................... 5-4
Drive chain, lubricating ................................................. 8-32Drive chain slack .......................................................... 8-30
E
Engine break-in .............................................................. 6-5
Engine, cold start ........................................................... 6-1
Engine idling speed ...................................................... 8-20
Engine oil ....................................................................... 5-3
Engine oil and oil filter element .................................... 8-10
Engine, starting a warm ................................................. 6-3
Engine stop switch ......................................................... 4-2
F
Fuel ........................................................................ 4-7
,
5-3
Fuel cock ........................................................................ 4-8
Fuel tank cap.................................................................. 4-7
Fuse, replacing............................................................. 8-37
H
Handlebar switches ........................................................ 4-2
Headlight beam, adjusting............................................ 8-41
Headlight bulb, replacing.............................................. 8-39
I
Identification numbers .................................................. 11-1
Indicator light .................................................................. 4-1
Instruments, lights and switches .................................... 5-7
K
Key identification number ............................................. 11-1
L
Label locations ............................................................... 2-1