2014 YAMAHA YZ450F oil

PRE-OPERATION INSPECTION AND MAINTENANCE
3-7
EAS1SL1067
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
EAS1SL1068GENERAL INSPECTION AND MAINTENANCE
TIP
Perform usual maintenance enough so that, in the race course, a confirmation of that and simple set-
ting adjustments may only be left, in order to get enough time to use effectively.
ITEMinspectPage
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.3-8 – 10
FuelCheck that a fresh gasoline is filled in the fuel tank.
Check the fuel line for leakage.1-22
Engine oilCheck that the oil level is correct. Check the crank-
case and oil line for leakage.3-14 – 16
Gear shifter and clutchCheck that gears can be shifted correctly in order and
that the clutch operates smoothly.3-10 – 11
Throttle grip/Housing
Check that the throttle grip operation and free play
are correctly adjusted. Lubricate the throttle grip and
housing, if necessary.
3-11 – 12
BrakesCheck the play of front brake and effect of front and
rear brake.3-21 – 27
Drive chainCheck drive chain slack and alignment. Check that
the drive chain is lubricated properly.3-27
4-64 – 65
WheelsCheck for excessive wear and tire pressure. Check
for loose spokes and have no excessive play.3-32 – 33
SteeringCheck that the handlebar can be turned smoothly and
have no excessive play.3-33 – 34
Front forks and rear
shock absorberCheck that they operate smoothly and there is no oil
leakage.3-28 – 32
Cables (wires)
Check that the clutch and throttle cables move
smoothly. Check that they are not caught when the
handlebars are turned or when the front forks travel
up and down.
—
Exhaust pipeCheck that the exhaust pipe is tightly mounted and
has no cracks.3-13 – 14
Rear wheel sprocketCheck that the rear wheel sprocket tightening bolt is
not loose.4-8 – 9
LubricationCheck for smooth operation. Lubricate if necessary. 3-12 , 3-34
Bolts and nutsCheck the chassis and engine for loose bolts and
nuts.1-25 – 26
Lead connectorsCheck that the AC magneto, ECU and ignition coil are
connected tightly.1-12 – 14
Settings
Is the machine set suitably for the condition of the rac-
ing course and weather or by taking into account the
results of test runs before racing? Are inspection and
maintenance completely done?10-1 – 8

ENGINE
3-12
LUBRICATING THE THROTTLE CABLE
1. Remove:• Cover (throttle cable cap) “1”
• Cover (grip cap) “2”
• Throttle grip cap “3”
2. Lubricate: • Throttle cable end “a”
3. Install: • Throttle grip cap
• Screw (throttle grip cap)
4. Install: • Cover (grip cap)
• Cover (throttle cable cap)
EWA
WARNING
Check that the throttle grip moves smooth-
ly. If this does not move smoothly, correct
the installed positions.
EAS1SL1080CLEANING THE AIR FILTER ELEMENT
1. Remove:• Fuel tank cap cover “1”Refer to “FUEL TANK CAP” on page 1-21.
• Air filter case cover “2” 2. Remove:
• Air filter mounting bolt “1”
• Air filter element “2”
• Air filter guide “3” (from the air filter element)
3. Wash: • Air filter element
EWA
WARNING
Do not use gasoline or organic (acid/alka-
line) volatile oil for washing.
TIP
After washing the element with air filter cleaner
or kerosene, squeeze and dry it completely.
ECA33DD016
NOTICE
Do not twist the element when squeezing
the element.
Recommended lubricant
Lithium-soap-based grease
Screw (throttle grip cap) 3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
T R..
1
2
13
2

ENGINE
3-13
4. Check:• Air filter elementDamage  Replace.
5. Foam-air-filter oil or equivalent oil to the ele- ment
TIP
Squeeze out the excess oil. Element should be
wet but not dripping.
6. Install:• Air filter guide “1” (to the air filter element)
• Air filter element “2”
• Air filter mounting bolt “3”
7. Install: • Air filter case cover “1”
• Air filter case cover mounting bolt
TIP
Align the air filter case cover groove “a” with the
air filter case edge “b”.
8. Install:• Fuel tank cap cover
EAS1SL1081
CHECKING THE THROTTLE BODY JOINT
1. Check:• Throttle body joint “1”
Refer to “CHECKING THE THROTTLE
BODY JOINT” on page 7-8.
EAS1SL1082CHECKING THE BREATHER HOSES
1. Check:• Breather hose “1”Crack/damage  Replace.
Loose connection  Connect properly.
ECA14920
NOTICE
Make sure that the breather hoses are rout-
ed correctly.
EAS1SL1083CHECKING THE EXHAUST SYSTEM
1. Remove:
• Exhaust pipe protector
2. Check:
• Exhaust pipe 1
• Exhaust pipe 2
• SilencerCrack/damage  Replace.
Refer to “ENGINE REMOVAL” on page 5-1.
• Exhaust gas
Leaks  Replace the gasket.
Refer to “ENGINE REMOVAL” on page 5-1.
3. Check:
• Tightening torques
Oil application quantify
50 g
Air filter mounting bolt 2 Nm (0.2 m·kgf, 1.4 ft·lbf)
Air filter case cover mounting bolt 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
T R..
31
2
T R..
a
b
1
Exhaust pipe bolt 1 and nut “1”
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Exhaust pipe 1 and exhaust pipe
2 bolt “2” 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Exhaust pipe 2 and silencer bolt
“3” 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Silencer and silencer bracket bolt
“4” 30 Nm (3.0 m·kgf, 22 ft·lbf)
1
T R..

ENGINE
3-14
4. Install:
• Exhaust pipe protector
EAS1SL1084CHECKING THE FUEL LINE
1. Remove:
• Seat
• Side cover (left/right)
• Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 4-
1.
• Fuel tank
Refer to “FUEL TANK” on page 7-1.
2. Check:
• Fuel hose “1”
Crack/damage  Replace.
Loose connection  Connect properly.
3. Install:
• Fuel tank
Refer to “FUEL TANK” on page 7-1.
• Air scoop (left/right)
• Seat
• Side cover (left/right)
Refer to “GENERAL CHASSIS” on page 4-
1.
EAS1SL1085CHECKING THE ENGINE OIL LEVEL
1. Stand the vehicle upright on a level surface.
2. Start the engine, warm this up for 2–3 min-
utes, and then stop the engine and wait
about 1 minute.
3. Check:
• Oil level
Make sure that the engine oil level is above
the minimum level mark “a” shown for the oil
level check window “1,” and that the engine
oil does not come out by removing the oil
check bolt “2.”
The minimum level mark “a” or below  Add
the engine oil until its level exceeds the min
-
imum level mark “a.”
Engine oil coming out of the oil check bolt 
Drain it until its last drop is out.
ECA33DD018
NOTICE
• Since engine oil also lubricates the clutch,
the wrong oil types or additives could
cause clutch slippage. Therefore, do not
add any chemical additives.
• Do not allow foreign material to enter the
crankcase.
Exhaust pipe protector screw
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
LOCTITE®
2
1
4
3
T R..
1
Recommended brand
YAMALUBE
Recommended engine oil type
SAE10W-30, SAE10W-40,
SAE10W-50, SAE15W-40,
SAE20W-40 or SAE20W-50
Recommended engine oil grade
API service SG type or higher,
JASO standard MA
12
a

ENGINE
3-15
EAS1SL1086CHANGING THE ENGINE OIL
Stand the vehicle upright on a level surface.
1. Start the engine, warm this up for several
minutes, and then stop the engine and wait
about 5 minutes.
2. Place an oil pan under the drain bolt.
3. Remove:
• Oil filler cap “1”
• Drain bolt (with gasket) “2”
4. If the oil filter element is also to be replaced,
perform the following procedure.
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a. Remove the oil filter element cover “1” and
oil filter element “2.”
b. Replace the O-rings “3.”
c. Install the new oil filter element and the oil fil-
ter element cover.
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5. To check the oil strainer, perform the follow-
ing procedure.
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a. Remove the oil strainer “1”.
b. Check the oil strainer.
Damage  Replace.
Clogging due to dirt  Wash with kerosene.
c. Replace the O-rings “2”.
d. Install the oil strainer.
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6. Install:
•Gaskets
• Drain bolt
1
2
Oil filter element cover bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil strainer bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Drain bolt
20 Nm (2.0 m·kgf, 14 ft·lbf)
1
3
2
New
T R..
1
2New
T R..
New
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ENGINE
3-16
7. Pour the specified amount of engine oil into
the oil filler cap hole.
8. Install:
• Oil filler cap
9. Check:
• Oil level
Refer to “CHECKING THE ENGINE OIL
LEVEL” on page 3-14.
10.Check:
• Engine oil pressure
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a. Slightly loosen the oil pressure check bolt
“1.”
EWA
WARNING
When the engine is started with the check
bolt removed, oil will spout; therefore, al
-
ways loosen it before the checkup.
Start the engine and keep it idling until oil
starts to seep from the oil pressure check
bolt.
EWA
WARNING
Always keep the engine idling speed during
the checkup without increasing the engine
speed.
ECA
NOTICE
If no engine oil seeps out after one minute,
immediately turn the engine off so it will not
seize.
b. If no engine oil seeps out, check the engine
oil for leaks, and the engine oil passage and
the oil pump for damage.
c. Check the oil pressure again.
d. Tighten the oil pressure check bolt.
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EAS1SL1087ADJUSTING THE ENGINE IDLING SPEED
TIP
• Because the air pressure is lower at high alti-
tudes, the air-fuel mixture will become richer.
If the idling speed is low, turn the starter knob/
idle screw a few clicks counterclockwise to in
-
crease the speed before the adjustment.
• Before adjusting the engine idling speed,
make sure that the air filter element is not
clogged, the engine compression is proper,
and the throttle grip free play is proper.
• Adjust the engine idling speed with the starter
knob/idle screw pushed in completely.
1. Start the engine, and warm this up until the
oil has reached the specified temperature.
2. Attach the pocket tester with temperature
probe “1” to the oil drain bolt.
3. Install:
• Digital tachometer
Engine oil quantity
With oil filter element replace-
ment
0.69 L (0.73 US qt, 0.61 Imp.qt)
Quantity (disassembled)
0.95 L (1.00 US qt, 0.84 Imp.qt)
1
Oil pressure check bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil temperature
55-65 °C (131–149 °F)
Digital tachometer
90890-06760
YU-39951-B
T R..
1

ENGINE
3-17
TIP
Get the high tension cord “1” of the ignition coil
pinched in the detector “a” of the digital tachom
-
eter.
4. Measure:
• Engine idling speed
Out of specification  Regulate.
5. Adjust:
• Engine idling speed
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a. Turn the starter knob/idle screw “1” in the di-
rection of “a” or “b” to make an adjustment.
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EAS1SL1088ADJUSTING THE VALVE CLEARANCE
TIP
• This section is intended for those who have
basic knowledge and skill concerning the ser
-
vicing of Yamaha motorcycles (e.g., Yamaha
dealers, service engineers, etc.). Those who
have little knowledge and skill concerning ser
-
vicing are requested not to undertake inspec-
tion, adjustment, disassembly, or reassembly
only by reference to this manual. It may lead to servicing trouble and mechanical damage.
• Make sure that the valve clearance is
checked or adjusted while the engine is cold
(at room temperature).
• While the valve clearance is checked or ad-
justed, make sure that the piston is positioned
in the top dead center (TDC).
1. Remove:
• Seat
• Side cover (left/right)
• Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 4-
1.
• Fuel tank
Refer to “FUEL TANK” on page 7-1.
•ECU
2. Remove:
• Spark plug
• Cylinder head cover
Refer to “CAMSHAFT” on page 5-11.
3. Remove:
• Timing mark accessing screw “1”
• Crankshaft end accessing screw “2”
• O-ring
4. Check:
• Valve clearance
Out of specification  Regulate.
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a. Turn the crankshaft counterclockwise with a
wrench.
b. Align the top dead center (TDC) mark “a” on
the rotor with the alignment mark “b” on the
crankcase cover.
Engine idling speed
1900–2100 r/min
Direction “a”Engine idling speed  De-
creases.
Direction “b”Engine idling speed  In-
creases.
1 1
a a
1 b
a
Valve clearance (cold)
Exhaust
0.20–0.25 mm (0.0079–0.0098 in)
1
2

ENGINE
3-19
d. Select an adjusting pad with a proper valve
clearance from the adjusting pad selection
table.
TIP
• There are 25 types of adjusting pads, ranging
from 1.20 mm (0.0472 in) to 2.40 mm (0.0945
in), in increments of 0.05 mm (0.0020 in).
• The field where the number on the originally
installed adjusting pad and the measured
valve clearance intersect shows the adjusting
pad number to replace.
Example:
Pad number = 148
Rounded value = 150
e. Install the new adjusting pads “4” and the
valve lifters “5.”
ECA@
NOTICE
Do not twist adjusting pads and valve lifters
forcibly during installation.
TIP
• Apply the engine oil on the valve lifters.
• Apply molybdenum disulfide oil to the valve
stem ends.
• Check that the valve lifters turn smoothly
when rotated with your finger.
• Make sure that valve lifters and adjusting
pads are installed in place.
• Make sure that adjusting pads are installed
with their numbers facing upward.
f. Install the camshafts (exhaust and intake).
Refer to “CAMSHAFT” on page 5-11.
g. Measure the valve clearance again.
h. If the valve clearance is out of specification,
repeat adjusting the valve clearance until it
is within specification.
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Last digit of pad
numberRounded valve
0, 1 or 20
4, 5 or 65
8 or 910
4 5