2008 YAMAHA WR 450F Owners Manual

Page 81 of 224

YAMAHA WR 450F 2008  Owners Manual 3-26
CHASSIS
LUBRICATION
To ensure smooth operation of all 
components, lubricate your machine 
during setup, after break-in, and after 
every race.
1. All control cable
2. Clutch lever pivot
3. Shift

Page 82 of 224

YAMAHA WR 450F 2008  Owners Manual 3-27
ELECTRICAL
ELECTRICAL
CHECKING THE SPARK PLUG
1. Remove:
• Spark plug
2. Inspect:
• Electrode "1"
Wear/damage→Replace.
• Insulator color "2"
Normal condition is a medium to 
light tan col

Page 83 of 224

YAMAHA WR 450F 2008  Owners Manual 3-28
ELECTRICAL
3. Remove:
• Battery band
•Battery
4. Measure:
• Battery charge
Measurement steps:
a. Connect a pocket tester "1" to the 
battery terminals.
• The charge state of an MF battery

Page 84 of 224

YAMAHA WR 450F 2008  Owners Manual 3-29
ELECTRICAL
Charging method using a variable voltage charger

Page 85 of 224

YAMAHA WR 450F 2008  Owners Manual 3-30
ELECTRICAL
Charging method using a constant voltage charger

Page 86 of 224

YAMAHA WR 450F 2008  Owners Manual 3-31
ELECTRICAL
6. Install:
•Battery
• Battery band
7. Connect:
• Battery leads
(to the battery terminals)
First, connect the positive lead "1", 
then the negative lead "2".
8. Check:
• Batter

Page 87 of 224

YAMAHA WR 450F 2008  Owners Manual 3-32
ELECTRICAL
ADJUSTING THE HEADLIGHT 
BEAMS
1. Adjust:
• Headlight beam (vertically)
Adjusting steps:
a. Turn the adjusting screw "1" in di-
rection "a" or "b".
Direction "a" Headlight beam is 
r

Page 88 of 224

YAMAHA WR 450F 2008  Owners Manual 4-1
ENGINE
TUNING
ENGINE
CARBURETOR SETTING
• The air/fuel mixture will vary de-
pending on atmospheric conditions. 
Therefore, it is necessary to take 
into consideration the air pressure, 
ambient