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
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Page 261 of 378

8-8 * It is recommended that these items be serviced by a Yamaha dealer.
** Lithium soap base grease.
NOTE:Recommended brake fluid: DOT 4
Brake fluid replacement:
1. When disassembling the master cylinder or caliper, replace the brake fluid. Normally check the brake
fluid level and add fluid as required.
2. On the inner parts of the master cylinder and caliper, replace the oil seals every two years.
3. Replace the brake hoses every four years, or if cracked or damaged.Wheels*•Check balance/damage/runout.
•Repair if necessary.Wheel bearings*•Check bearing assemblies for looseness/damage.
•Replace if damaged.Front and rear
suspension*•Check operation.
•Correct if necessary.Steering system*•Check operation.
•Correct if damaged.
•Check toe-in.
•Adjust if necessary.Steering shaft*
•Lubricate every 6 months**.Fittings and Fasteners*•Check all chassis fittings and fasteners.
•Correct if necessary.Battery*•Check specific gravity.
•Check that the breather hose is working properly.
•Correct if necessary.
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
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8-53 1. Locknut 2. Adjusting bolt
1. Contre-écrou 2. Boulon de réglage
1. Contratuerca 2. Perno de ajuste
1. Brake cable adjusting nut
a. Gap: 0–1 mm
1.Écrou de réglage du câble de frein
a. Jeu: 0 à 1 mm
1. Tuerca de ajustado del cable de freno
a. Separación: 0–1 mm
Brake lever
1. Loosen the locknut and fully turn in the ad-
justing bolt on the handlebar.
2. Turn the adjusting nut on brake cable to pro-
vide a gap of 0–1 mm between the cam shaft
lever and pin.
U4XE64.book Page 53 Thursday, May 30, 2002 1:49 PM
Page 316 of 378
8-63
EBU00717
Brake lever and brake pedal lubrication
Lubricate the pivoting parts.
EBU00370
Steering shaft lubrication
Lubricate the pivot points. Use a grease gun.Recommended lubricant:
Lithium-soap-based grease
(all-purpose grease)
Recommended lubricant:
Lithium soap base grease
U4XE64.book Page 63 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