open YAMAHA WR 450F 2006 User Guide

3 - 52
INSP
ADJ
BATTERY INSPECTION AND CHARGING
ÈRelationship between the open-circuit voltage
and the charging time at 20 °C (68 °F)
(These values vary with the temperature, the
condition of the battery plates, and the electro-
lyte level.)
ÉOpen-circuit voltage
ÊCharging time (hours)
ËTime (minutes)
ÌCharging condition of the battery
ÍAmbient temperature 20 °C (68 °F)
aCharging
bCheck the open-circuit voltage.
5. Charge:
Battery
(refer to the appropriate charging method
illustration)
WARNING
Do not quick charge a battery.
CAUTION:
Never remove the MF battery sealing
caps.
Do not use a high-rate battery charger
since it forces a high-amperage current
into the battery quickly and can cause
battery overheating and battery plate
damage.
If it is impossible to regulate the charging
current on the battery charger, be careful
not to overcharge the battery.
When charging a battery, be sure to
remove it from the machine. (If charging
has to be done with the battery mounted
on the machine, disconnect the negative
battery lead from the battery terminal.)
To reduce the chance of sparks, do not
plug in the battery charger until the bat-
tery charger leads are connected to the
battery. Check the charge of the battery, as shown
in the charts and the following example.
Example
Open-circuit voltage = 12.0 V
Charging time = 6.5 hours
Charge of the battery = 20 ~ 30%
È

3 - 53
INSP
ADJ
BATTERY INSPECTION AND CHARGING
Before removing the battery charger lead
clips from the battery terminals, be sure
to turn off the battery charger.
Make sure the battery charger lead clips
are in full contact with the battery termi-
nal and that they are not shorted. A cor-
roded battery charger lead clip may
generate heat in the contact area and a
weak clip spring may cause sparks.
If the battery becomes hot to the touch at
any time during the charging process,
disconnect the battery charger and let the
battery cool before reconnecting it. Hot
batteries can explode!
As shown in the following illustration, the
open-circuit voltage of an MF battery sta-
bilizes about 30 minutes after charging
has been completed. Therefore, wait
30 minutes after charging is completed
before measuring the open-circuit volt-
age.

3 - 54
INSP
ADJ
BATTERY INSPECTION AND CHARGING
Charging method using a variable voltage charger
Connect a charger and
ammeter to the battery
and start charging.
Is the amperage higher
than the standard charg-
ing amperage written on
the battery?NO YES Charger
Ammeter
Adjust the voltage to obtain
the standard charging amper-
age.
Set the timer to the charging
time determined by the open-
circuit voltage.
Refer to “BATTERY
INSPECTION AND CHARG-
ING” section.Adjust the charging voltage to
20 ~ 25 V.
Monitor the amperage for 3 ~
5 minutes. Is the standard
charging amperage exceeded?
NO YES
If the amperage does not
exceed the standard charg-
ing amperage after 5 minutes,
replace the battery.
If the required charging time exceeds 5 hours, it is advisable to check
the charging amperage after 5 hours. If there is any change in the
amperage, readjust the voltage to obtain the standard charging amper-
age.
Leave the battery unused for more than 30 minutes before measuring
its open-circuit voltage.
12.8 V
→ Charging is complete.
12.0 ~ 12.7 V
→ Recharging is required.
Under 12.0 V
→ Replace the battery.
Leave the battery unused for
more than 30 minutes before
measuring its open-circuit voltage.
Set the charging voltage to 16-
17 V. (If the charging voltage is
lower, charging will be insuffi-
cient, if it is higher, the battery will
be over-charged.) NOTE:
NOTE:
Measure the open-circuit
voltage prior to charging.

3 - 55
INSP
ADJ
BATTERY INSPECTION AND CHARGING
Charging method using a constant voltage charger
Measure the open-circuit
voltage prior to charging.
Connect a charger and
ammeter to the battery
and start charging.
NO
YESIs the amperage higher
than the standard charg-
ing amperage written on
the battery?
Charge the battery until the charging
voltage reaches 15 V.
Leave the battery unused for more than
30 minutes before measuring its open-cir-
cuit voltage.
12.8 V
→ Charging is complete.
12.0 ~ 12.7 V
→ Recharging is required.
Under 12.0 V
→ Replace the battery.This type of battery charger cannot
charge an MF battery. A variable
voltage charger is recommended.
Leave the battery unused for
more than 30 minutes before
measuring its open-circuit voltage. NOTE:
Set the charging time to a maxi-
mum of 20 hours. NOTE:
Constant amperage chargers
are not suitable for charging
MF batteries.
CAUTION:
Charger
Ammeter
Voltmeter

4 - 6
ENGRADIATOR
EC456000
HANDLING NOTE
WARNING
Do not remove the radiator cap when the
engine and radiator are hot. Scalding hot
fluid and steam may be blown out under
pressure, which could cause serious
injury.
When the engine has cooled, open the radi-
ator cap by the following procedure:
Place a thick rag, like a towel, over the radi-
ator cap, slowly rotate the cap counter-
clockwise to the detent. This procedure
allows any residual pressure to escape.
When the hissing sound has stopped,
press down on the cap while turning coun-
terclockwise and remove it.
EC454000
INSPECTION
EC444100
Radiator
1. Inspect:
Radiator core 1
Obstruction → Blow out with compressed
air through rear of the radiator.
Bent fin → Repair/replace.
EC455000
ASSEMBLY AND INSTALLATION
Radiator
1. Install:
Pipe 1 1
Hose 1 2
Pipe 2 3
Hose 3 4
Hose 4 5
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
2. Install:
Hose 2 1
Radiator (left) 2
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

5 - 64
CHAS
EC586000
HANDLING NOTE
WARNING
This shock absorber is provided with a
separate type tank filled with high-pressure
nitrogen gas. To prevent the danger of
explosion, read and understand the follow-
ing information before handling the shock
absorber.
The manufacturer can not be held respon-
sible for property damage or personal
injury that may result from improper han-
dling.
1. Never tamper or attempt to disassemble
the cylinder or the tank.
2. Never throw the shock absorber into an
open flame or other high heat. The
shock absorber may explode as a result
of nitrogen gas expansion and/or dam-
age to the hose.
3. Be careful not to damage any part of the
gas tank. A damaged gas tank will impair
the damping performance or cause a
malfunction.
4. Take care not to scratch the contact sur-
face of the piston rod with the cylinder;
or oil could leak out.
5. Never attempt to remove the plug at the
bottom of the nitrogen gas tank. It is
very dangerous to remove the plug.
6. When scrapping the shock absorber, fol-
low the instructions on disposal.
EC587000
NOTES ON DISPOSAL (YAMAHA DEALERS
ONLY)
Before disposing the shock absorber, be sure
to extract the nitrogen gas from valve 1. Wear
eye protection to prevent eye damage from
escaping gas and/or metal chips.
WARNING
To dispose of a damaged or worn-out
shock absorber, take the unit to your
Yamaha dealer for this disposal procedure.
REAR SHOCK ABSORBER

–+ELEC
6 - 2
MAP-CONTROLLED CDI UNIT
MAP-CONTROLLED CDI UNIT
A map-controlled, CDI ignition system is used in the WR450F.
The microcomputer in the CDI unit detects the engine speed and throttle position, thus determining
the optimum ignition timing through the entire operating range. In this way, quick throttle response
can be achieved according to various riding conditions.
Throttle position sensorCDI unitIgnition coil
Pickup coilAC magneto rotor

Function of Component
Component Function
TPS
(throttle position sensor)Detects throttle valve opening and inputs it into the computer in the
CDI unit as a throttle opening signal.
Pickup coil Detects signal rotor revolutions and inputs them into the computer in
the CDI unit as engine revolution signals.
CDI unit The signals of the TPS and pickup coil sensor are analyzed by the
computer in the CDI unit, which then adjusts ignition timing for the
operation requirements.

Principal of 3-Dimensional Control
Conventionally, ignition timing was controlled only
by engine revolutions (2-dimensional control).
However, ignition timing needs advancement also
by engine load. Thus, accurate ignition timing can
be determined by adding throttle opening to deter-
mine ignition timing (3-dimensional control).
3-D Image Map of Ignition Timing
(different from actual characteristics)
Ignition timing
Th
rot
t
le
o
peni
ngRev
o
lut
io
ns

6 - 7
–+ELEC
ELECTRIC STARTING SYSTEM
STARTING CIRCUIT CUT-OFF SYSTEM
OPERATION
If the main switch is set to “ON”, the starter
motor can only operate if at least one of the fol-
lowing conditions is met:
•The transmission is in neutral (the neutral
switch is closed).
•The clutch lever is pulled to the handlebar
(the clutch switch is closed).
The starting circuit cut-off relay prevents the
starter motor from operating when neither of
these conditions has been met. In this
instance, the starting circuit cut-off relay is
open so current cannot reach the starter
motor. When at least one of the above condi-
tions has been met the starting circuit cut-off
relay is closed and the engine can be started
by pressing the start switch.
WHEN THE TRANSMISSION IS
IN NEUTRAL
WHEN THE CLUTCH LEVER IS
PULLED TO THE HANDLEBAR
1Battery
2Main fuse
3Main switch
4Starting circuit cut-off relay
5Start switch
6Diode
7Clutch switch
8Neutral switch
9Starter relay
0Starter motor
12
M
3
4
5
8 76 9
0
ELECTRIC STARTING SYSTEM

6 - 21
–+ELECTPS (THROTTLE POSITION SENSOR) SYSTEM
3. Inspect:
•TPS coil variable resistance
Check that the resistance in increased as
the throttle grip is moved from the full
close position to the full open position.
Out of specification → Replace.
Tester (+) lead
→ Yellow lead
1
Tester (–) lead
→ Black lead
2
TPS coil variable
resistanceTester selec-
tor position
Full closed Full opened
k
Ω
× 1 0 ~ 2 k
Ω
at 20 °C
(68°F)4 ~ 6 k
Ω
at 20 °C
(68°F)
TPS REPLACEMENT AND ADJUSTMENT
1. Remove:
•TPS coupler
•Screw (TPS) 1
•TPS 2
NOTE:
Loosen the screws (TPS) using the T25 bit.
2. Replace:
•TPS
3. Install:
•TPS 1
•Screw (TPS) 2
•TPS coupler
NOTE:
•Align the slot a in the TPS with the projec-
tion b on the carburetor.
•Temporarily tighten the screws (TPS).
12
21
b
a

7 - 2
TUN
CAUTION:
The carburetor is extremely sensitive to
foreign matter (dirt, sand, water, etc.).
During installation, do not allow foreign
matter to get into the carburetor.
Always handle the carburetor and its
components carefully. Even slight
scratches, bends or damage to carburetor
parts may prevent the carburetor from
functioning correctly. Carefully perform
all servicing with the appropriate tools
and without applying excessive force.
When the engine is stopped or when
riding at no load, do not open and close
the throttle unnecessarily. Otherwise, too
much fuel may be discharged, starting
may become difficult or the engine may
not run well.
After installing the carburetor, check that
the throttle operates correctly and opens
and closes smoothly.
Atmospheric conditions and carburetor
settings
The air density (i.e., concentration of oxygen
in the air) determines the richness or lean-
ness of the air/fuel mixture. Therefore, refer
to the above table for mixture settings.
That is:
•Higher temperature expands the air with its
resultant reduced density.
•Higher humidity reduces the amount of oxy-
gen in the air by so much of the water vapor
in the same air.
•Lower atmospheric pressure (at a high alti-
tude) reduces the density of the air.
Air temp. HumidityAir
pressure
(altitude)Mixture Setting
High High Low (high) Richer Leaner
Low Low High (low) Leaner Richer
SETTING