Page 17 of 378

OPERATION ...........................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine ........................6-9
Warming up ..........................................6-9
Drive select lever operation and
reverse driving .................................6-11
Shifting ...............................................6-15
To start out and accelerate: ................6-17
To decelerate: ....................................6-19
Engine break-in ..................................6-21
Parking ...............................................6-23
Parking on a slope .............................6-25
Accessories and loading ....................6-27
RIDING YOUR ATV..................................7-1
Getting to know your ATV .....................7-3
Ride with care and good
judgement ...........................................7-5
Be careful where you ride ...................7-27
Turning your ATV ................................7-41
Climbing uphill.....................................7-47
Riding downhill ....................................7-57
Crossing a slope .................................7-61
Crossing through shallow water ..........7-65
Riding over rough terrain ....................7-69
Sliding and skidding ............................7-71
67
What to do if ....................................... 7-75
What to do .......................................... 7-75
PERIODIC MAINTENANCE AND
ADJUSTMENT ......................................... 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication ......... 8-7
Engine oil ............................................ 8-13
Final gear oil ....................................... 8-21
Spark plug inspection ......................... 8-27
Air filter cleaning ................................. 8-31
Carburetor adjustment ....................... 8-37
Idle speed adjustment ....................... 8-39
Valve clearance adjustment .............. 8-41
Throttle lever adjustment ................... 8-41
Front brake pad inspection ................ 8-43
Rear brake shoe inspection ............... 8-43
Brake fluid level inspection ................ 8-45
Brake fluid replacement ...................... 8-47
Front brake adjustment ...................... 8-49
Rear brake adjustment ....................... 8-51
Adjusting the rear brake light switch ... 8-57
Clutch adjustment .............................. 8-59
Cable inspection and lubrication......... 8-61
Brake lever and brake pedal
lubrication ........................................ 8-63
Steering shaft lubrication ................... 8-63
8
U4XE64.book Page 2 Thursday, May 30, 2002 1:49 PM
Page 124 of 378
5-15
CAUTION:_
In order to prevent clutch slippage (since
the engine oil also lubricates the clutch),
do not mix any chemical additives. Do not
use oils with a diesel specification of “CD”
or oils of a higher quality than specified. In
addition, do not use oils labeled “ENERGY
CONSERVING II” or higher.
Make sure that no foreign material enters
the crankcase.
_
Oil quantity:
Periodic oil change:
1.5 L
With oil filter element replacement:
1.6 L
Total amount:
1.8 L
U4XE64.book Page 15 Thursday, May 30, 2002 1:49 PM
Page 152 of 378
6-15 1. Shift pedal N. Neutral position
1. Pédale de sélection N. Point mort
1. Pedal del cambio N. Punto muerto
EBU00201
Shifting
This model has a 5-speed forward and 1-speed re-
verse transmission with centrifugal automatic
clutch. The transmission allows you to control the
amount of power you have available at a given
speed or for starting accelerating, climbing, etc. To
shift into neutral, return the throttle lever to its orig-
inal position and repeatedly depress the shift ped-
al until it stops.CAUTION:
Do not coast for long periods with the engine
off, and do not tow the machine a long dis-
tance. Even with gears in neutral, the transmis-
sion is only properly lubricated when the
engine is running. Inadequate lubrication may
damage the transmission.
U4XE64.book Page 15 Thursday, May 30, 2002 1:49 PM
Page 210 of 378

7-37
With the engine idling, lift the shift pedal to the 1st
gear position and then release the parking brake.
Apply the throttle slowly and smoothly. The centrif-
ugal clutch will engage and you will start to accel-
erate. Once the ATV has attained adequate
speed, release the throttle and lift the shift pedal to
the 2nd gear position. Release the shift pedal and
apply the throttle smoothly. Use this same proce-
dure as you move into the higher gears. Be sure to
coordinate the use of the throttle and shift pedal
properly. If the throttle is applied too abruptly or if
the throttle is not released during shifting, or if the
shift pedal is not released before applying the
throttle, the front wheels may lift off the ground re-
sulting in a loss of directional control. Avoid higher
speeds until you are thoroughly familiar with the
operation of your ATV.CAUTION:
Do not shift gears without releasing the throt-
tle. Damage to the engine or drive train may oc-
cur.
U4XE64.book Page 37 Thursday, May 30, 2002 1:49 PM
Page 260 of 378

8-7
EBU00262
PERIODIC MAINTENANCE/LUBRICATION
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
Valves*•Check valve clearance.
•Adjust if necessary.
Spark plug•Check condition.
•Adjust gap and clean.
•Replace if necessary.Air filter•Clean.
•Replace if necessary.Every 20–40 hours
(More often in wet or dusty areas.)
Carburetor*•Check idle speed/starter operation.
•Adjust if necessary.Cylinder head breather
system*•Check breather hose for cracks or damage.
•Replace if necessary.Exhaust system*•Check for leakage.
•Retighten if necessary.
•Replace gasket if necessary.Fuel line*•Check fuel hose for cracks or damage.
•Replace if necessary.Engine oil
•Replace (Warm engine before draining).Engine oil filter
•Clean.Engine oil strainer
•Clean.Final gear oil•Check oil level/oil leakage.
•Replace.Front brake*•Check operation/fluid leakage/see NOTE page 8-8.
•Correct if necessary.Rear brake*•Check operation.
•Adjust if necessary.Clutch*•Check operation.
•Adjust if necessary.U4XE64.book Page 7 Thursday, May 30, 2002 1:49 PM
Page 312 of 378
8-59 1. Locknut 2. Adjusting bolt
1. Contre-écrou 2. Boulon de réglage
1. Contratuerca 2. Perno de ajuste
EBU00346
Clutch adjustment
1. Loosen the locknut.
2. Slowly turn the adjusting bolt counterclock-
wise until resistance is felt. Then, turn it 1/8
turn clockwise.
3. Tighten the locknut to specification.NOTE:Turn the adjusting bolt counterclockwise to de-
crease the clutch free play and turn it clockwise to
increase the free play.
Tightening torque:
15 Nm (1.5 m·kgf)
U4XE64.book Page 59 Thursday, May 30, 2002 1:49 PM
Page 358 of 378
10-3
Air filter: Dry type element
Fuel:
Type For Europe: Regular unleaded gasoline only
For Australia: Unleaded gasoline only
Tank capacity 12 L
Reserve amount 1.6 L
Carburetor:
Type / manufacturer BST34/1/MIKUNI
Spark plug:
Type / manufacturer DR7EA / NGK
Gap 0.6–0.7 mm
Clutch type: Wet, centrifugal automatic
Transmission:
Primary reduction system Spur gear
Primary reduction ratio 73/22 (3.318)
Secondary reduction system Shaft drive
Secondary reduction ratio 19/18
× 46/11 (4.414)
Transmission type Constant mesh, 5-speed forward, 1-speed reverse
Operation Left foot operationModel YFM250X
U4XE64.book Page 3 Thursday, May 30, 2002 1:49 PM