2005 YAMAHA YFZ450 cooling

OPERATION ............................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine .........................6-9
Warming up...........................................6-9
Shifting ................................................6-11
To start out and accelerate .................6-13
To decelerate ......................................6-17
Engine break-in ...................................6-19
Parking ................................................6-23
Parking on a slope ..............................6-25
Accessories and loading .....................6-29
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
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............ 8-17
Engine oil and oil filter element........... 8-23
Cooling system ................................... 8-41
Changing the coolant.......................... 8-45
Spark plug inspection ......................... 8-53
Air filter element cleaning ................... 8-65
Carburetor adjustment ........................ 8-73
Idle speed adjustment ........................ 8-75
Valve clearance adjustment ............... 8-75
Throttle lever adjustment .................... 8-77
Front brake pad inspection ................. 8-79
Rear brake pad inspection.................. 8-81
Brake fluid level inspection ................. 8-83
Brake fluid replacement ...................... 8-87
Front brake lever free play.................. 8-89
Brake pedal height adjustment ........... 8-91
Parking brake adjustment ................... 8-93
Adjusting the rear brake light switch ... 8-97
Clutch lever free play adjustment ....... 8-99
Drive chain slack check .................... 8-101
Drive chain slack adjustment ............ 8-103
Lubricating the drive chain................ 8-107
Cable inspection and lubrication....... 8-111
8
U5TG61.book Page 2 Friday, April 2, 2004 11:28 AM

6-21
0–10 hours:
Avoid continuous operation above half throttle. Al-
low a cooling off period of five to ten minutes after
every hour of operation. Vary the speed of the ma-
chine from time to time. Do not operate it at one
set throttle position.
10–20 hours:
Avoid prolonged operation above 3/4 throttle. Rev
the machine freely through the gears but do not
use full throttle at any time.
After break-in:
Avoid prolonged full throttle operation. Vary
speeds occasionally.
U5TG61.book Page 21 Friday, April 2, 2004 11:28 AM

8-7
EBU02621
PERIODIC MAINTENANCE/LUBRICATION
NOTE:_

For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.


For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance in-
tervals. However, keep in mind that if the ATV isn’t used for a long period of time, the month mainte-
nance intervals should be followed.
_
ITEM ROUTINEWhichever
comes firstINITIAL EVERY
month136612
km
(mi)320
(200)1,200
(750)2,400
(1,500)2,400
(1,500)4,800
(3,000)
hours 20 75 150 150 300
Valves*Check valve clearance.
Adjust if necessary.
Cooling systemCheck for coolant leakage.
Repair if necessary.
Replace coolant every 24 months.Spark plugCheck condition.
Adjust gap and clean.
Replace if necessary.Air filter elementClean.
Replace if necessary.Every 20–40 hours
(More often in wet or dusty areas.)
Carburetor*Check starter (choke) operation.
Adjust engine idling speed.Crankcase breather
system*Check breather hose for cracks or damage.
Replace if necessary.Exhaust system*Check for leakage.
Tighten 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).U5TG61.book Page 7 Friday, April 2, 2004 11:28 AM

8-41 1. Maximum level mark 2. Minimum level mark
3. Coolant reservoir 4. Coolant reservoir cap
1. Repère de niveau maximum 2. Repère de niveau minimum
3. Vase d’expansion 4. Bouchon du vase d’expansion
1. Marca de nivel máximo 2. Marca de nivel mínimo
3. Depósito de refrigerante
4. Tapa del depósito de líquido refrigerante
EBU10151
Cooling system
1. Check the coolant level in the coolant reser-
voir when the engine is cold as the coolant
level will vary with engine temperature.NOTE:_ The coolant should be between the minimum and
maximum level marks. _2. If the coolant is at or below the minimum level
mark, remove the coolant reservoir cap, and
then add coolant or distilled water to raise it to
the specified level.CAUTION:_ Hard water or salt water is harmful to the en-
gine. You may use soft water if you can’t get
distilled water. _
Coolant reservoir capacity
(up to the maximum level mark):
0.29 L
U5TG61.book Page 41 Friday, April 2, 2004 11:28 AM

8-47 1. Coolant reservoir cap 2. Coolant reservoir
3. Bolt (× 2)
1. Bouchon du vase d’expansion 2. Vase d’expansion
3. Boulon (× 2)
1. Tapa del depósito de líquido refrigerante
2. Depósito de refrigerante
3. Perno (× 2)
5. Remove the coolant reservoir by removing
the bolts.
6. Remove the coolant reservoir cap, and then
turn the coolant reservoir upside down to
empty it.
7. After draining the coolant, thoroughly flush
the cooling system with clean tap water.
8. Install the coolant reservoir by installing the
bolts.
9. Replace the coolant drain bolt washer if it is
damaged, and then tighten the coolant drain
bolt to the specified torque.
10. Pour the recommended coolant into the radi-
ator until it is full.
11. Pour the recommended coolant into the cool-
ant reservoir to the maximum level mark. Tightening torque:
Coolant drain bolt:
10 Nm (1.0 m·kgf)
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8-51
CAUTION:_ Hard water or salt water is harmful to the en-
gine. You may use soft water if you cannot get
distilled water. _12. Install the radiator cap and the coolant reser-
voir cap.
13. Start the engine and let it idle for several min-
utes. Stop the engine, and then check the
coolant level in the radiator. If it is low, add
more coolant until it reaches the top of the ra-
diator.
14. Check the coolant level in the reservoir. If it is
low, add coolant to the maximum level mark.
15. Start the engine and then check for coolant
leakage.NOTE:_ If any leakage is found, have a Yamaha dealer
check the cooling system. _16. Install the panel.
U5TG61.book Page 51 Friday, April 2, 2004 11:28 AM

8-148
Engine overheatingNOTE:_ If it is difficult to get the recommended coolant, tap water can be temporarily used, provided that it is
changed to the recommended coolant as soon as possible. _
WARNING
_ Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap. _ Wait until the
engine has cooled.
Check the coolant level in the
coolant reservoir and/or radiator.
Level is OK.Level is low, check the
cooling system for leakage.
No
leakage.Leakage.
Ask a Yamaha dealer to inspect
and repair the cooling system.Add coolant. (See NOTE.)
Restart the engine. If the engine overheats again, ask a
Yamaha dealer to inspect and/or repair the cooling system.
U5TG61.book Page 148 Friday, April 2, 2004 11:28 AM