2004 YAMAHA WR 450F checking oil

GEN
INFO
1 - 8
SPECIAL TOOLS
YM-01442, 90890-01442 Fork seal driver
This tool is used when install the fork oil seal.YM-01442 90890-01442
YS-1880-A, 90890-01701 Sheave holder
This tool is used for when loosening or tightening the
flywheel magneto securing nut.YS-1880-A 90890-01701
YU-3112-C, 90890-03112 Yamaha pocket tester
Use this tool to inspect the coil resistance, output
voltage and amperage.YU-3112-C 90890-03112
YM-33277-A, 90890-03141 Timing light
This tool is necessary for checking ignition timing.YM-33277-A 90890-03141
YM-4019, 90890-04019 Valve spring compressor
This tool is needed to remove and install the valve
assemblies.YM-4019 90890-04019
YM-91042, 90890-04086 Clutch holding tool
This tool is used to hold the clutch when removing or
installing the clutch boss securing nut.YM-91042 90890-04086
YM-4116, 90890-04116
YM-4097, 90890-04097Valve guide remover
Intake 4.5 mm (0.18 in)
Exhaust 5.0 mm (0.20 in)
This tool is needed to remove and install the valve
guide.YM-4116
YM-409790890-04116
90890-04097
YM-4117, 90890-04117
YM-4098, 90890-04098Valve guide installer
Intake
Exhaust
This tool is needed to install the valve guide.YM-4117
YM-409890890-04117
90890-04098
YM-4118, 90890-04118
YM-4099, 90890-04099Valve guide reamer
Intake 4.5 mm (0.18 in)
Exhaust 5.0 mm (0.20 in)
This tool is needed to rebore the new valve guide.YM-4118
YM-4099 90890-04118
90890-04099
Part number Tool name/How to use Illustration

3 - 14
INSP
ADJ
ENGINE OIL LEVEL INSPECTION
ENGINE OIL LEVEL INSPECTION
1. Stand the motorcycle on a level surface.
NOTE:
When checking the oil level make sure that
the motorcycle is upright.
Place the motorcycle on a suitable stand.
WARNING
Never remove the oil tank cap just after
high speed operation. The heated oil could
spurt out. causing danger. Wait until the oil
cools down to approximately 70 ˚C (158 ˚F).
2. Idle the engine more than 3 minutes
while keeping the motorcycle upright.
Then stop the engine and inspect the oil
level.
3. Remove:
Oil tank cap 1
1
4. Inspect:
Oil level
Oil level should be between maximum
a and minimum b marks.
Oil level low → Add oil to proper level.
NOTE:
When inspecting the oil level, do not screw the
oil level gauge into the oil tank.
Insert the gauge lightly.
a
b

3 - 18
INSP
ADJ
PILOT SCREW ADJUSTMENT
10. Install:
Oil filler plug
11. Inspect:
Engine (for oil leaks)
Oil level
Refer to “ENGINE OIL LEVEL INSPEC-
TION”.
12. Check:
Oil pressure
PILOT SCREW ADJUSTMENT
1. Adjust:
Pilot screw 1
* Except for USAChecking steps:
Slightly loosen the oil gallery bolt 1.
Start the engine and keep it idling until oil
starts to seep from the oil gallery bolt. If no
oil comes out after one minute, turn the
engine off so it will not seize.
Check oil passages, oil filter and oil pump
for damage or leakage.
Start the engine after solving the prob-
lem(s) and recheck the oil pressure.
Tighten the oil gallery bolt to specification.
T R..
Oil gallery bolt:
10 Nm (1.0 m • kg, 7.2 ft • lb)
Adjusting steps:
NOTE:
To optimize the fuel flow at a smaller throttle
opening, each machine’s pilot screw has
been individually set at the factory. Before
adjusting the pilot screw, turn it in fully and
count the number of turns. Record this num-
ber as the factory-set number of turns out.
Turn in the pilot screw until it is lightly
seated.
Turn out the pilot screw by the factory-set
number of turns.
Pilot screw:
1-3/4 turns out (example)
*1-1/2 turns out (example)

4 - 26
ENGCAMSHAFTS
Decompression system
1. Check:
Decompression system
Checking steps:
Check that the decompressor cam 1
moves smoothly.
Check that the decompressor lever pin 2
projects from the camshaft.
Timing chain tensioner
1. Check:
While pressing the tensioner rod lightly
with fingers, use a thin screwdriver 1
and wind the tensioner rod up fully
clockwise.
When releasing the screwdriver by
pressing lightly with fingers, make sure
that the tensioner rod will come out
smoothly.
If not, replace the tensioner assembly.
ASSEMBLY AND INSTALLATION
1. Install:
Exhaust camshaft 1
Intake camshaft 2
Installation steps:
Turn the crankshaft counterclockwise until
the “I” mark a on the rotor is aligned with
the stationary pointer b on the crankcase
cover.
NOTE:
Apply the molybdenum disulfide oil on the
camshafts.
Apply the engine oil on the decompression
system.

5 - 36
CHASFRONT FORK
19. Wait ten minutes until the air bubbles
have been removed from the front fork,
and the oil has dispense evenly in system
before setting recommended oil level.
NOTE:
Fill with the fork oil up to the top end of the
outer tube, or the fork oil will not spread over to
every part of the front forks, thus making it
impossible to obtain the correct level.
Be sure to fill with the fork oil up to the top of
the outer tube and bleed the front forks.
20. Measure:
Oil level (left and right) a
Out of specification → Adjust.
* For EUROPE, AUS, NZ and ZA
NOTE:
Be sure to install the spring guide 2 when
checking the oil level.
WARNING
Never fail to make the oil level adjustment
between the maximum and minimum level
and always adjust each front fork to the
same setting. Uneven adjustment can
cause poor handling and loss of stability.
Standard oil level:
125 mm (4.92 in)
* 130 mm (5.12 in)
Extent of adjustment:
80 ~ 150 mm (3.15 ~ 5.91 in)
From top of outer tube with
inner tube and damper rod 1
fully compressed without
spring.

–+ELEC

6 - 3
IGNITION SYSTEM
EC620000
IGNITION SYSTEM
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to
ignition system failure and for checking the spark plug which will not spark.
*1 marked: Refer to “FUSE INSPECTION” section in the CHAPTER 3.
*2 marked: Refer to “BATTERY INSPECTION AND CHARGING” section in the CHAPTER 3.
*3 marked: Only when the ignition checker is used.
NOTE:


Remove the following parts before inspection.
1) Seat
2) Fuel tank

Use the following special tools in this inspection.
Dynamic spark tester:
YM-34487
Ignition checker:
90890-06754
Pocket tester:
YU-3112-C/90890-03112
*1 Check fuse.Replace fuse and
check wire harness.
*2 Check battery Recharge or replace.
Spark gap test*3 Clean or replace
spark plug.
Check entire ignition
system for connection.
(couplers, leads and
ignition coil)Repair or replace.
Check “ENGINE STOP”
button.Replace.
Check main switch. Replace.
Check ignition coil. Primary coil Replace.
Secondary coil Replace.
Check AC magneto. Pick-up coil Replace.
Check neutral switch. Repair or replace.
Replace CDI unit.
OK
OK
No spark
OK
OK
OK
OK
OK
OK
Spark
No good
No good
No good
No good
No good
No good
No good
No good
No good

6 - 18
–+ELECCHARGING SYSTEM
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
Couplers and leads connection
Rust/dust/looseness/short-circuit →
Repair or replace.
CHARGING VOLTAGE INSPECTION
1. Start the engine.
2. Inspect:
Charging voltage
Out of specification → If no failure is
found in checking the source coil resis-
tance, replace the rectifier/regulator.
Tester (+) lead → Red lead 1
Tester (–) lead → Black lead 2
Charging
voltageTester selector
position
14.1 ~ 14.9 V at
5,000 r/minDCV-20
R
BW Y1
2
3. Inspect:
Charging coil resistance
Out of specification → Replace.
Tester (+) lead → White lead 1
Tester (–) lead → Ground 2
Charging coil
resistanceTester selector
position
0.288 ~ 0.432 Ω
at 20 ˚C (68 ˚F)Ω × 1