2008 YAMAHA WR 450F clock

1-9
MULTI-FUNCTION DISPLAY
COLD STARTER KNOB
When cold, the engine requires a
richer air-fuel mixture for starting. A
separate starter circuit, which is con-
trolled by the cold starter knob "1",
supplies this mixture. Pull the cold
starter knob out to open the circuit for
starting. When the engine has
warmed up, push it in to close the cir-
cuit.
HOT STARTER LEVER
The hot starter lever "1" is used when
starting a warm engine. Use the hot
starter lever when starting the engine
again immediately after it was
stopped (the engine is still warm).
Pulling the hot starter lever injects
secondary air to thin the air-fuel mix-
ture temporarily, allowing the engine
to be started more easily.
SIDESTAND
This sidestand "1" is used to support
only the machine when standing or
transporting it.
• Never apply additional force to
the sidestand.
• Hold up the sidestand before
starting out.
MULTI-FUNCTION DISPLAY
Be sure to stop the machine before
making any setting changes to the
multi-function display.
The multi-function display is
equipped with the following:
BASIC MODE:
• Speedometer
•Clock
• Two tripmeters (which shows the
distance that has been traveled
since it was last set to zero)
RACE MODE:
• Timer (which shows the time that
has been accumulated since the
start of timer measurement)
• Tripmeter (which shows the accu-
mulated travel distance in timer
measurement)
• Change tripmeter digits (capable of
change to any given ones)
DESCRIPTION
Operation buttons:
1. Select button "SLCT 1"
2. Select button "SLCT 2"
3. Reset button "RST"
Screen display:
4. Tripmeter indicator
5. Tripmeter indicator
6. Timer indicator
7. Clock/Timer
8. Speedometer
9. Odometer/Tripmeter
The operation buttons can be pushed
in the following two manners:
Short push: Push the button. ( )
Long push: Push the button for 2 sec-
onds or more. ( )
BASIC MODE
Changing speedometer display
(for U.K.)
1. Push the "SLCT2" button for 2
seconds or more to change the
speedometer units. The speed-
ometer display will change in the
following order:
MPH→km/h→MPH.Setting the time
1. Push the "SLCT1" button for 2
seconds or more to enter the time
setting mode.
2. Push the "RST" button to change
the display for time indication.
The display will change in the fol-
lowing order:
Hour→Minute→Second→Hour.
The digits capable of setting go on
flashing.
3. Push the "SLCT1" button (plus) or
"SLCT2" button (minus) and
change the time. A long push on
the button will fast-forward the
time.
4. To end the setting, push the
"RST" button for 2 seconds or
more.
• In a 30-second absence of button
operation, the setting will come to
an end with the indicated time.
• To reset the seconds, push the
"SLCT1" button or "SLCT2" button.
Changing odometer and tripmeter
A/B (TRIP A/B)
1. Push the "SLCT2" button to
change the tripmeter display. The
display will change in the follow-
ing order:
Odometer →TRIP A→TRIP B→
TRIP A→Odometer.

1-12
MULTI-FUNCTION DISPLAY
FUNCTION DIAGRAM
A short push on the button changes
the operation in the arrowed direction.
A short push on the button changes
the operation in both arrowed directions.
A long push on the button changes the
operation in the arrowed direction.
A long push on the button changes the
operation in both arrowed directions.Meter function
Function that can be performed whether
the time is or is not in operation.
Extent to which the meter can operate
Clock
BASIC MODE
Tripmeter
ODO TRIP A TRIP B ODO
Speedometer
(for U.K.)
MPH
km/h MPH
Putting measurement on
standby
Manual startAuto start
RACE MODE
Timer in operation
Reset
TRIP ACorrect
TRIP AMeasurement starts as the
machine moves
Timer not in
operation
Correct
TRIP AReset
TRIP A &
timer

1-13
MULTI-FUNCTION DISPLAY
The following diagram illustrates the
multi-function display regarding the
direction and operation condition in-
volved in each of its functions.
A. A short push on the button
changes the operation in the ar-
rowed direction.
B. A short push on the button
changes the operation in both
arrowed directions.
C. A long push on the button
changes the operation in the ar-
rowed direction.
D. A long push on the button
changes the operation in both
arrowed directions.
E. Meter function
F. Function that can be performed
whether the time is or is not in
operation.
G. Extent to which the meter can
operate
1.BASIC MODE
2. Clock
3. Trip meter
4. Speedometer (for U.K.)
5.RACE MODE
6. Putting measurement on stand-
by
7. Manual start
8. Auto start
9. Measurement starts as the ma-
chine moves
10. Timer in operation
11. Reset TRIP A
12. Correct TRIP A
13. Timer not in operation
14. Reset TRIP A & timer

2-6
MAINTENANCE SPECIFICATIONS
Stem runout limit ---- 0.01 mm
(0.0004 in)
Valve spring:
Free length (IN) 39.46 mm (1.55 in) 38.46 mm (1.51
in)
Free length (EX) 37.61 mm (1.48 in) 36.61 mm (1.44
in)
Set length (valve closed) (IN) 27.87 mm (1.10 in) ----
Set length (valve closed) (EX) 28.38 mm (1.12 in) ----
Compressed force (installed) (IN) 130.2–149.8 N at 27.87 mm (13.28–15.28
kg at 27.87 mm, 29.27–33.68 lb at 1.10 in)----
Compressed force (installed) (EX) 123.1–141.7 N at 28.38 mm (12.55–14.45
kg at 28.38 mm, 27.67–31.85 lb at 1.12 in)----
Tilt limit* (IN) ---- 2.5°/1.7 mm
(2.5°/0.067 in)
Tilt limit* (EX) ---- 2.5°/1.6 mm
(2.5°/0.063 in)
Direction of winding (top view) (IN) Clockwise ----
Direction of winding (top view) (EX) Clockwise ----
Piston:
Piston to cylinder clearance 0.020–0.045 mm (0.0008–0.0018 in) 0.1 mm (0.004
in)
Piston size "D" 94.965–94.980 mm (3.7388–3.7394 in) ----
Measuring point "H" 8 mm (0.315 in) ----
Piston off-set 1 mm (0.0394 in) ----
Piston pin bore inside diameter 18.004–18.015 mm (0.7088–0.7093 in) 18.045 mm
(0.7104 in)
Piston pin outside diameter 17.991–18.000 mm (0.7083–0.7087 in) 17.971 mm
(0.7075 in) Item Standard Limit

3-9
ENGINE
CHECKING THE SILENCER AND
EXHAUST PIPE
1. Inspect:
• Gasket "1"
Damage→Replace.
INSTALLING THE SILENCER AND
EXHAUST PIPE
1. Install:
• Gasket
• Exhaust pipe "1"
• Nut (exhaust pipe) "2"
• Bolt (exhaust pipe) "3"
First, temporarily tighten the nut (ex-
haust pipe), then tighten the bolt (ex-
haust pipe) 13 Nm (1.3 m•kg, 9.4
ft•lb). After that, retighten the nut (ex-
haust pipe) 20 Nm (2.0 m•kg, 14 ft•lb)
and then the bolt (exhaust pipe) 20
Nm (2.0 m•kg, 14 ft•lb).
2. Install:
• Silencer clamp "1"
• Gasket "2"
• Silencer
• Washer "4"
• Bolt (silencer) "5"CHECKING THE COOLANT LEVEL
Do not remove the radiator cap
"1", drain bolt and hoses when the
engine and radiator are hot. Scald-
ing hot fluid and steam may be
blown out under pressure, which
could cause serious injury. When
the engine has cooled, place a
thick towel over the radiator cap,
slowly rotate the cap counter-
clockwise to the detent. This pro-
cedure allows any residual
pressure to escape. When the
hissing sound has stopped, press
down on the cap while turning
counterclockwise and remove it.
Hard water or salt water is harmful
to the engine parts. You may use
distilled water, if you can't get soft
water.
1. Place the machine on a level
place, and hold it in an upright po-
sition.
2. Remove:
• Radiator cap
3. Check:
• Coolant level "a"
Coolant level low→Add coolant.
1. Radiator
CHANGING THE COOLANT
Do not remove the radiator cap
when the engine is hot.
Take care so that coolant does not
splash on painted surfaces. If it
splashes, wash it away with water.
1. Place a container under the en-
gine.
2. Remove:
• Seat
• Left side cover
3. Remove the catch tank hose from
the catch tank and drain the tank
of its coolant.
4. Remove:
• Coolant drain bolt "1"
5. Remove:
• Radiator cap
Drain the coolant completely.
6. Clean:
• Cooling system
Thoroughly flush the cooling sys-
tem with clean tap water.
7. Install:
• Copper washer
• Coolant drain bolt
8. Fill:
•Radiator
• Engine
To specified level.
• Do not mix more than one type of
ethylene glycol antifreeze con-
taining corrosion inhibitors for
aluminum engine.
• Do not use water containing im-
purities or oil.
Nut (exhaust pipe):
20 Nm (2.0 m•kg, 14
ft•lb)
Bolt (exhaust pipe):
20 Nm (2.0 m•kg, 14
ft•lb)
Silencer clamp:
16 Nm (1.6 m•kg, 11
ft•lb)
Bolt (silencer):
30 Nm (3.0 m•kg, 22
ft•lb)
Coolant drain bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Recommended coolant:
High quality ethylene
glycol anti-freeze con-
taining anti-corrosion
for aluminum engine
Coolant "1" and water
(soft water) "2" mixing ra-
tio:
50%/50%
Coolant capacity:
1.0 L (0.88 Imp qt, 1.06
US qt)

3-14
ENGINE
ADJUSTING THE PILOT SCREW
1. Adjust:
• Pilot screw "1"
Adjustment steps:
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 number
as the factory-set number of turns
out.
a. Turn in the pilot screw until it is
lightly seated.
b. Turn out the pilot screw by the
factory-set number of turns.
ADJUSTING THE ENGINE IDLING
SPEED
1. Start the engine and thoroughly
warm it up.
2. Adjust:
• Engine idling speed
Adjustment steps:
a. Turn the throttle stop screw "1"
until the specified engine idling
speed.
Using a digital engine tachometer for
idle speed adjustment, detect the en-
gine idling speed by bringing the
sensing element "c" of the engine ta-
chometer close to the ignition coil "2".
ADJUSTING THE VALVE
CLEARANCE
• The valve clearance should be ad-
justed 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 "REMOVING THE SEAT,
FUEL TANK AND SIDE COV-
ERS" section.
2. Remove:
• Air cut-off valve assembly
Refer to "AIR INDUCTION SYS-
TEM" section in the CHAPTER 5.
• Spark plug
• Engine upper bracket
• Cylinder head cover
Refer to "CAMSHAFTS" section
in the CHAPTER 5.
3. Remove:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw
"2"
• O-ring4. Check:
• Valve clearance
Out of specification→Adjust.
Checking steps:
a. Turn the crankshaft counterclock-
wise with a wrench.
b. 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.
In order to be sure that the piston is at
Top Dead Center, the punch mark "c"
on the exhaust camshaft and the
punch mark "d" on the intake cam-
shaft must align with the cylinder
head surface, as shown in the illustra-
tion.
c. Measure the valve clearance "e"
using a feeler gauge "1".
Record the measured reading if the
clearance is incorrect.
Pilot screw (example):
2 turns out
(For EUROPE)
To increase idle speed→Turn the
throttle stop screw "1" in "a".
To decrease idle speed→Turn the
throttle stop screw "1" out "b".
Engine idling speed:
1,750–1,950 r/min
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)

3-15
ENGINE
5. Adjust:
• Valve clearance
Adjustment steps:
a. Remove the camshaft (intake and
exhaust).
Refer to "CAMSHAFTS" section
in the CHAPTER 5.
b. Remove the valve lifters "1" and
the pads "2".
• Place a rag in the timing chain
space to prevent pads from falling
into the crankcase.
• Identity each valve lifter and pad
position very carefully so that they
can be reinstalled in their original
place.
c. Select the proper pad using the
pad selecting table.
The thickness "a" of each pad is indi-
cated in hundredths of millimeters on
the pad upper surface.
d. Round off the last digit of the in-
stalled pad number to the nearest
increment.
EXAMPLE:
Installed pad number = 148
Rounded off value = 150
Pads can only be selected in 0.05
mm increments.
e. Locate the rounded-off value and
the measured valve clearance in
the chart "PAD SELECTION TA-
BLE". The field where these two
coordinates intersect shows the
new pad number to use.
Use the new pad number only as a
guide when verifying the valve clear-
ance adjustment.
f. Install the new pads "3" and the
valve lifters "4".
• Apply the engine oil on the valve lift-
ers.
• Apply the molybdenum disulfide oil
on the valve stem ends.
• Valve lifter must turn smoothly
when rotated with a finger.
• Be careful to reinstall valve lifters
and pads in their original place.
g. Install the camshafts (exhaust
and intake).
Refer to "CAMSHAFTS" section
in the CHAPTER 5.h. Install the timing chain tensioner.
Refer to "CAMSHAFTS" section
in the CHAPTER 5.
Turn the crankshaft counterclockwise
several turns so that the installed
parts settle into the right position.
i. Recheck the valve clearance.
j. If the clearance is still incorrect,
repeat all the clearance adjust-
ment steps until the specified
clearance is obtained.
6. Install:
• All removed parts
Install all removed parts in reversed
order of their removal.
Pad rangePad Availabili-
ty: 25 incre-
ments
No.
120–
No.
2401.20
mm–
2.40
mmPads are avail-
able in 0.05 mm
increments
Last digit of pad
numberRounded valve
0, 1 or 2 0
4, 5 or 6 5
8 or 9 10
Bolt (camshaft cap):
10 Nm (1.0 m•kg, 7.2
ft•lb)

3-21
CHASSIS
When installing the drive chain, apply
the lithium soap base grease on the
chain joint and O-rings.
7. Install:
• Link plate
• Press the link plate onto the chain
joint using a drive chain riveter "5".
• Rivet the end of the chain joint us-
ing a drive chain riveter.
• After riveting the chain joint, make
sure its movement is smooth.
8. Lubricate:
• Drive chain
ADJUSTING THE DRIVE CHAIN
SLACK
1. Elevate the rear wheel by placing
the suitable stand under the en-
gine.
2. Check:
• Drive chain slack "a"
Above the seal guard installation
bolt.
Out of specification→Adjust.
Before checking and/or adjusting, ro-
tate the rear wheel through several
revolutions and check the slack sev-
eral times to find the tightest point.
Check and/or adjust the drive chain
slack with the rear wheel in this "tight
chain" position.
3. Adjust:
• Drive chain slack
Drive chain slack adjustment
steps:
a. Loosen the axle nut "1" and lock-
nuts "2".
b. Adjust the drive chain slack by
turning the adjusters "3".
c. Turn each adjuster exactly the
same amount to maintain correct
axle alignment. (There are marks
"a" on each side of the drive chain
puller alignment.)
Turn the adjuster so that the drive
chain is in line with the sprocket, as
viewed from the rear.
Too small drive chain slack will
overload the engine and other vital
parts; keep the slack within the
specified limits.
d. Tighten the axle nut while pushing
down the drive chain.e. Tighten the locknuts.
CHECKING THE FRONT FORK
1. Inspect:
• Front fork smooth action
Operate the front brake and
stroke the front fork.
Unsmooth action/oil leakage→
Repair or replace.
CLEANING THE FRONT FORK OIL
SEAL AND DUST SEAL
1. Remove:
•Protector
• Dust seal "1"
Use a thin screw driver, and be care-
ful not to damage the inner fork tube
and dust seal.
2. Clean:
• Dust seal "a"
• Oil seal "b"
• Clean the dust seal and oil seal af-
ter every run.
• Apply the lithium soap base grease
on the inner tube.
RELIEVING THE FRONT FORK
INTERNAL PRESSURE
If the front fork initial movement feels
stiff during a run, relieve the front fork
internal pressure.
Drive chain lubricant:
SAE 10W-30 motor oil
or suitable chain lubri-
cants
Drive chain slack:
48–58 mm (1.9–2.3 in)
To tighten→Turn the adjuster "3"
counterclockwise.
To loosen→Turn the adjuster "3"
clockwise and push wheel for-
ward.
Axle nut:
125 Nm (12.5 m•kg, 90
ft•lb)
Locknut:
19 Nm (1.9 m•kg, 13
ft•lb)