Page 17 of 446

Tire wear limit......................................5-31
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
Engine break-in ...................................6-17
Parking ................................................6-19
Parking on a slope ..............................6-21
Accessories and loading .....................6-23
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 ................................7-39
Climbing uphill.....................................7-45
Riding downhill ....................................7-55
Crossing a slope .................................7-59
Crossing through shallow water ..........7-63
Riding over rough terrain ....................7-69
Sliding and skidding ............................7-71
What to do if ........................................7-75
What to do...........................................7-75
67
PERIODIC MAINTENANCE AND
ADJUSTMENT ........................................ 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Panel removal and installation............ 8-15
Engine oil and oil filter cartridge ......... 8-31
Final gear oil ....................................... 8-41
Differential gear oil.............................. 8-47
Cooling system ................................... 8-53
Changing the coolant.......................... 8-57
Axle boots ........................................... 8-63
Spark plug inspection ......................... 8-65
Air filter element cleaning ................... 8-71
V-belt cooling duct check hose ........... 8-79
V-belt case drain plug ......................... 8-79
Carburetor adjustment ........................ 8-81
Idle speed adjustment ........................ 8-83
Valve clearance adjustment ............... 8-85
Throttle lever adjustment .................... 8-87
Front brake pad check ........................ 8-89
Rear brake pad check ........................ 8-91
Inspecting the brake fluid level ........... 8-93
Brake fluid replacement ...................... 8-97
Front brake lever free play.................. 8-99
Rear brake lever adjustment ............ 8-101
Brake pedal position adjustment ...... 8-101
8
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Page 56 of 446
3-1
EBU00032
DESCRIPTION AND MACHINE
IDENTIFICATION1. Rear shock absorber
assembly spring preload
adjusting ring
2. Storage compartment
and tool kit
3. Spark plug
4. Rear brake fluid reservoir
5. Radiator cap
6. Front shock absorber
assembly spring preload
adjusting ring
7. V-belt case
8. Brake pedal
9. Front shock absorber
assembly spring preload
adjusting ring
10. Fuel cock
11. Air filter case
12. Fuses13. Tail/brake light
14. V-belt cooling duct check
hose
15. Coolant reservoir
16. Oil filter cartridge
17. Engine oil dipstick
18. Rear brake lever
19. Left handlebar switches
20. Starter (choke)
21. Horn switch
22. Drive select lever
23. Speedometer unit
24. Main switch
25. Fuel tank cap
26. Auxiliary DC jack
27. Right handlebar switch
28. Throttle lever
29. Front brake leverNOTE:The machine you have purchased may differ
slightly from those shown in the figures of this
manual.
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Page 260 of 446
7-65
1. Air filter case check hose
1. Flexible de contrôle du boîtier de filtre à air
1. Manguera de comprobación de la caja del filtro de aire
Test your brakes after leaving the water. Do not
continue to ride your ATV without verifying that
you have regained proper braking ability.CAUTION:_ After riding your ATV in water, be sure to drain
the trapped water by removing the check hose
at the bottom of the air filter case, the V-belt
cooling duct check hose, the drive select lever
box check hose and the storage compartment
check hose. Also, remove the V-belt case drain
plug to drain any water that may have accumu-
lated. Wash the ATV in fresh water if it has
been operated in salt water or muddy condi-
tions. _
U5ND61.book Page 65 Thursday, June 5, 2003 7:02 PM
Page 262 of 446
7-67 1. V-belt cooling duct check hose
1. Flexible de contrôle du conduit de refroidissement de la courroie
trapézoïdale
1. Manguera de comprobación del conducto de enfriamiento de
la correa trapezoidal
1. Drive select lever box check hose
1. Flexible de contrôle du boîtier du levier de présélection
1. Manguera de comprobación de la caja de la palanca de
selección de marcha
1. Storage compartment check hose
1. Flexible de contrôle du compartiment de rangement
1. Manguera de comprobación del compartimiento porta objetos
1. V-belt case drain plug
1. Boulon de vidange du carter de courroie trapézoïdale
1. Tapón de drenaje de la caja de la correa trapezoidal
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Page 283 of 446

8-8
* Since these items require special tools, data and technical skills, have a Yamaha dealer perform the service.NOTE:
Recommended brake fluid: DOT 4
Brake fluid replacement:
When disassembling the master cylinders or caliper cylinders, replace the brake fluid. Normally
check the brake fluid level and add fluid as required.
On the inner parts of the master cylinders and caliper cylinders, replace the oil seals every two years.
Replace the brake hoses every four years, or if cracked or damaged.
V-belt*Check operation.
Check for cracks or damage.Wheels*Check balance/damage/runout.
Repair if necessary.Wheel bearing*Check bearing assemblies for looseness/damage.
Replace if damaged.Front and rear
suspension*Check operation.
Correct if necessary.Steering system*Check operation./Replace if damaged.
Check toe-in./Adjust if necessary.Drive shaft universal
joint*Lubricate with lithium-soap-based grease.Engine mount*
Check for cracks or damage.Axle boots*Check operation.
Replace if damaged.Fittings and fasteners*Check all chassis fittings and fasteners.
Correct if necessary.Lights and switches*Check operation.
Adjust headlight beams.
ITEM ROUTINEWhichever
comes firstINITIAL EVERY
km 320 1,200 2,400 2,400 4,800
hours 20 75 150 150 300
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8-79 1. V-belt cooling duct check hose
1. Flexible de contrôle du conduit de refroidissement de la courroie
trapézoïdale
1. Manguera de comprobación del conducto de enfriamiento de
la correa trapezoidal
1. V-belt case drain plug
1. Boulon de vidange du carter de courroie trapézoïdale
1. Tapón de drenaje de la caja de la correa trapezoidal
EBU06411
V-belt cooling duct check hose
If dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.
EBU08741
V-belt case drain plug
After riding in water deep enough to allow it to en-
ter the V-belt case, remove this plug to drain the
water from the case.NOTE:_ If water drains from the V-belt case after removing
the plug, have a Yamaha dealer inspect the ATV
as the water may affect other engine parts. _
U5ND61.book Page 79 Thursday, June 5, 2003 7:02 PM
Page 427 of 446
10-4
Spark plug:
Type/manufacturer DR8EA / NGK
Spark plug gap 0.6–0.7 mm
Clutch type: Wet, centrifugal automatic
Transmission:
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)
Sub transmission ratio low 45/16 (2.813)
high 38/23 (1.652)
Chassis:
Frame type Steel tube frame
Caster angle 4°
Trail 21 mm
Tire:
Ty p e T u b e l e s s
Size front AT25
×8 - 12
rear AT25
× 10 - 12 ModelYFM450FA
U5ND61.book Page 4 Thursday, June 5, 2003 7:02 PM