engine YAMAHA YFM250R 2011 Workshop Manual

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)U1BT61E0.book Page 2 Tuesday, April 6, 2010 1:28 PM

10-1
10
EBU25960
SPECIFICATIONS
Dimensions:Overall length:
1625 mm (64.0 in)
Overall width:
1072 mm (42.2 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)Noise and vibration level:Noise level (77/311/EEC):
YFM25RA 81.0 dB(A)@3500 r/min
YFM25RSEA 81.0 dB(A)@3500 r/min
Noise level 40 CFR Part 205 Subpart D (Acceleration):
YFM25RA 78.8 dB(A)
YFM25RSEA 78.8 dB(A)
Vibration on seat (EN1032, ISO5008):
YFM25RA Will not exceed 0.5 m/s²
YFM25RSEA Will not exceed 0.5 m/s²Vibration on handlebar (EN1032, ISO5008):
YFM25RA Will not exceed 2.5 m/s²
YFM25RSEA Will not exceed 2.5 m/s²
Engine:Engine type:
Air cooled 4-stroke, SOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
249 cm³
Bore × stroke:
74.0 × 58.0 mm (2.91 × 2.28 in)
Compression ratio:
9.50 :1
Starting system:
Electric starter
Lubrication system:
Wet sumpEngine oil:Recommended brand:
YAMALUBE
U1BT61E0.book Page 1 Tuesday, April 6, 2010 1:28 PM

10-2
10
Type:
SAE 5W-30, 10W-30, 10W-40, 15W-40, 20W-40 or 20W-
50
Recommended engine oil grade:
API service SG type or higher, JASO standard MA
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:
YFM250RA Unleaded gasoline only
YFM250RSEA Unleaded gasoline only
YFM25RA Regular unleaded gasoline only
YFM25RSEA Regular unleaded gasoline only
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:Type × quantity:
BSR29 x 1Spark 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 operationTransmission:Primary reduction system:
Spur gear
Primary reduction ratio:
76/22 (3.455)
Secondary reduction system:
Chain drive
0 10 30 50 70 90 110 130 ˚F
–20 –10 0 10 20 30 40 50 ˚CSAE 5W-30
SAE 10W-30
SAE 10W-40
SAE 15W-40
SAE 20W-40SAE 20W-50
U1BT61E0.book Page 2 Tuesday, April 6, 2010 1:28 PM

INDEX
AAccessories and loading ................................................ 6-6
Air filter element, cleaning ............................................ 8-14BBattery .......................................................................... 8-35
Brake and clutch levers, checking and lubricating ....... 8-32
Brake fluid, changing .................................................... 8-25
Brake fluid level, checking ............................................ 8-23
Brake lever free play, checking the front ...................... 8-25
Brake lever (YFM25RA/YFM250RA) ............................. 4-5
Brake lever (YFM25RSEA/YFM250RSEA) .................... 4-5
Brake light switches ..................................................... 8-27
Brake pads, checking the front and rear ...................... 8-22
Brake pedal .................................................................... 4-6
Brake pedal, checking and lubricating ......................... 8-33
Brake pedal position, checking .................................... 8-25
Brakes .......................................................................... 8-22
Brakes, front and rear .................................................... 5-3CCables, checking and lubricating ................................. 8-31
Carburetor, adjusting .................................................... 8-20
Chassis fasteners ........................................................... 5-6
Cleaning ......................................................................... 9-1
Clutch lever .................................................................... 4-4
Clutch lever free play, adjusting ................................... 8-28DDrive chain ..................................................................... 5-4
Drive chain, lubricating ................................................. 8-31Drive chain slack .......................................................... 8-29
EEngine break-in .............................................................. 6-4
Engine, cold start ........................................................... 6-1
Engine idling speed ...................................................... 8-20
Engine oil ....................................................................... 5-3
Engine oil and oil filter element .................................... 8-11
Engine, starting a warm ................................................. 6-2
Engine stop switch ......................................................... 4-2FFuel ......................................................................... 4-8, 5-3
Fuel cock ...................................................................... 4-10
Fuel tank cap .................................................................. 4-8
Fuse, replacing ............................................................. 8-38HHandlebar switches ........................................................ 4-2
Headlight beam, adjusting ............................................ 8-41
Headlight bulb, replacing .............................................. 8-39IIdentification numbers .................................................. 11-1
Indicator light .................................................................. 4-2
Instruments, lights and switches .................................... 5-6LLabel locations ............................................................... 1-1
Light switch .................................................................... 4-3MMain switch .................................................................... 4-1
Maintenance and lubrication chart ................................. 8-5
U1BT61E0.book Page 1 Tuesday, April 6, 2010 1:28 PM