2007 YAMAHA WR 450F fuel

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SPECCABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1Fuel tank breather hose
2Clamp
3Diode
4Hot starter cable
5Throttle position sensor lead
6Wire harness
7Hump (frame)
8Negative battery lead
9Starter motor lead
0Neutral switch lead
AAC magneto lead
BBrake hose
CRectifier/regulator leadDCarburetor breather hose
ECarburetor overflow hose
FCatch tank breather hose

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SPECCABLE ROUTING DIAGRAM
ÈInsert the end of the fuel tank breather hose into
the hole in the steering stem.
ÉFasten the throttle cable, hot starter cable and
rectifier/regulator lead onto the frame. Locate
the clamp end facing the lower side of the hot
starter cable and cut off the tie end.
ÊFasten the diode (at the marking), throttle cable
and hot starter cable onto the frame. Locate the
clamp end facing toward the lower right of the
frame and with the tie end facing downward.
ËFasten the wire harness, throttle position sensor
lead and clutch cable onto the frame. Pass the
clamp through the hole in the stay (air cut-off
valve). Locate the clamp end facing toward the
lower side of the frame and cut off the tie end.ÌFasten the throttle position sensor lead onto the
frame. Locate the clamp end facing toward the
lower side of the frame and cut off the tie end.
ÍPass the carburetor breather hoses, carburetor
overflow hose and catch tank breather hose
between the connecting rod and cross tube
(frame).
ÎPass the neutral switch lead on the inside of the
engine bracket.
ÏFasten the neutral switch lead and AC magneto
lead onto the frame. Locate the clamp end fac-
ing toward the outside of the frame and tie end
facing toward the rear of the frame.

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INSP
ADJ
MAINTENANCE INTERVALS
ROTOR NUT
Retighten
MUFFLER
Inspect and retighten
Clean
Replace * Whichever comes first
*SPARK ARRESTER
(Every six
months)
Clean
CRANK
Inspect and clean
CARBURETOR
Inspect, adjust and clean
AIR INDUCTION SYSTEM
Inspect and clean
SPARK PLUG
Inspect and clean
Replace
DRIVE CHAIN
Use chain lube
Chain slack: 48 ~ 58 mm
(1.9 ~ 2.3 in) Lubricate, slack, alignment
Replace
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolant Every two years
Inspect hoses
OUTSIDE NUTS AND BOLTS Refer to “STARTING
AND BREAK-IN” section
in the CHAPTER 1. Retighten
AIR FILTER
Use foam air-filter oil or
equivalent oil Clean and lubricate
Replace
OIL FILTER
Replace
OIL STRAINER (frame)
Clean
FRAME
Clean and inspect
FUEL TANK, COCK
Clean and inspect
BRAKES
Adjust lever position and pedal height
Lubricate pivot point
Check brake disc surface
Check fluid level and leakage
Retighten brake disc bolts, caliper
bolts, master cylinder bolts and union
bolts
Replace pads
Replace brake fluid Every one yearItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks


3

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INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
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.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator filler cap.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-21
Engine oilCheck that the oil level is correct. Check the crankcase and oil
line for leakage.P.3-14 ~ 18
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-9 ~ 10
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-10 ~ 11
Brakes Check the play of front brake and effect of front and rear brake. P.3-25 ~ 31
ChainCheck chain slack and alignment. Check that the chain is lubri-
cated properly.P.3-32 ~ 35
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-43 ~ 44
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-44 ~ 46
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-35 ~ 42
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.—
Muffler Check that the muffler is tightly mounted and has no cracks.—
Sprocket Check that the driven sprocket tightening bolt is not loose. P.3-32
Lubrication Check for smooth operation. Lubricate if necessary. P.3-47
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-26
Lead connectorsCheck that the AC magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 20

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INSP
ADJ
VALVE CLEARANCE ADJUSTMENT
VALVE CLEARANCE ADJUSTMENT
NOTE:
The valve clearance should be adjusted
when the engine is cool to the touch.
The piston must be at Top Dead Center
(T.D.C.) on compression stroke to check or
adjust the valve clearance.
1. Remove:
Seat
Fuel tank
Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
2. Remove:
Air cut-off valve assembly
Refer to “AIR INDUCTION SYSTEM”
section in the CHAPTER 4.
Spark plug
Engine stay (upper)
Cylinder head cover
Refer to “CAMSHAFTS” section in the
CHAPTER 4.
3. Remove:
Timing plug 1
Straight plug 2
O-ring
1
2
4. Check:
Valve clearance
Out of specification → Adjust.
Valve clearance (cold):
Intake valve:
0.10 ~ 0.15 mm
(0.0039 ~ 0.0059 in)
Exhaust valve:
0.20 ~ 0.25 mm
(0.0079 ~ 0.0098 in)
Checking steps:
Turn the crankshaft counterclockwise with
a wrench.
Align the T.D.C. mark a on the rotor with
the align mark b on the crankcase cover
when piston is at T.D.C. on compression
stroke.
b
a

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INSP
ADJ
Install the handlebar so that the projection
c of the handlebar holder (upper) is posi-
tioned at the mark on the handlebar as
shown.
Insert the end of the fuel breather hose B
into the hole in the steering shaft.
CAUTION:
First tighten the bolts on the front side of
the handlebar holder (upper), and then
tighten the bolts on the rear side.
T R..
Steering shaft nut:
145 Nm (14.5 m  kg, 105 ft  lb)
Handlebar holder (upper):
28 Nm (2.8 m  kg, 20 ft  lb)
Pinch bolt (handle crown):
21 Nm (2.1 m  kg, 15 ft  lb)
Headlight:
7 Nm (0.7 m  kg, 5.1 ft  lb)
STEERING HEAD INSPECTION AND ADJUSTMENT

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INSP
ADJ
REPLACING THE HEADLIGHT BULBS
3. Replace:
Blown fuse
WARNING
Never use a fuse with an amperage rating
other than that specified. Improvising or
using a fuse with the wrong amperage rat-
ing may cause extensive damage to the
electrical system, cause the starting and
ignition systems to malfunction and could
possibly cause a fire.
4. Install:
Fuse cover
Seat Replacement steps:
Set the main switch to “OFF”.
Install a new fuse of the correct amperage.
Set on the switches to verify if the electri-
cal circuit is operational.
If the fuse immediately blows again, check
the electrical circuit.
ItemsAmperage
ratingQ’ty
Main fuse 10 A 1
REPLACING THE HEADLIGHT BULBS
1. Remove:
Headlight
Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
2. Remove:
Headlight bulb holder cover 1
3. Remove:
Headlight bulb holder 1
NOTE:
Remove the headlight bulb holder by pushing
it in and turning it counterclockwise.

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INSP
ADJ
ADJUSTING THE HEADLIGHT BEAMS
4. Remove:
Headlight bulb
WARNING
Since the headlight bulb gets extremely
hot, keep flammable products and your
hands away from the bulb unit it has cooled
down.
5. Install:
Headlight bulb
CAUTION:
Avoid touching the glass part of the head-
light bulb to keep it free form oil, otherwise
the transparency of the glass, the life of the
bulb and the luminous flux will be
adversely affected. If the headlight bulb
gets soiled, thoroughly clean it with a cloth
moistened with alcohol or lacquer thinner.
6. Install:
Headlight bulb holder
7. Install:
Headlight bulb holder cover
8. Install:
Headlight
Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
New
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
ADJUSTING THE HEADLIGHT BEAMS
1. Adjust:
Headlight beam (vertically)
Adjusting steps:
Turn the adjusting screw 1 in direction a
or b.
Direction a Headlight beam is raised.
Direction bHeadlight beam is lowered.