2016 YAMAHA WR 450F Owners Manual

CHASSIS
3-39
EAS2GC1127LUBRICATING THE DRIVE CHAIN
The drive chain consists of many interacting
parts. If the drive chain is not maintained prop-
erly, it will wear out quickly. Therefore, the drive
chain should be serviced, especially when the
vehicle is used in dusty areas.
This vehicle has a drive chain with small rubber
O-rings between each side plate. Steam clean-
ing, high-pressure washing, certain solvents,
and the use of a coarse brush can damage
these O-rings. Therefore, use only kerosene to
clean the drive chain. Wipe the drive chain dry
and thoroughly lubricate it with engine oil or
chain lubricant that is suitable for O-ring chains.
Do not use any other lubricants on the drive
chain since they may contain solvents that
could damage the O-rings.
EAS2GC1128LUBRICATING THE SIDESTAND
Lubricate the pivoting point and metal-to-metal
moving parts of the sidestand.
EAS2GC1129CHECKING THE CHASSIS FASTENERS
Make sure that all nuts, bolts, and screws are
properly tightened.
Refer to “CHASSIS TIGHTENING TORQUES”
on page 2-17.Recommended lubricant
Chain lubricant suitable for O-
ring chains
Recommended lubricant Lithium-soap-based grease

ELECTRICAL SYSTEM
3-40
EAS2GC1130
ELECTRICAL SYSTEM
EAS2GC1131CHECKING THE SPARK PLUG
1. Remove:• Seat
• Air scoop (left/right)
Refer to “GENERAL CHASSIS” on page 5-
1.
• Fuel tank “1” Refer to “FUEL TANK” on page 8-1.
ECA
NOTICE
Do not use too much force to pull the hose.
TIP
Remove the fuel tank, turn this 180 ° clockwise,
and put it in the frame “2” as shown.
2. Remove:• Spark plug cap
• Spark plugRefer to “CAMSHAFT” on page 6-11.
ECA
NOTICE
In order not to allow the dirt accumulated
around the spark plug to drop from the
spark plug hole into the cylinder, clean it be-
fore removing the spark plug.
3. Check:• Spark plug type
Wrong type  Replace.
4. Check: • ElectrodeDamage/wear  Replace the spark plug.
• Insulator Abnormal color  Replace the spark plug.
Normal color is medium-to-light tan. 5. Clean:
• Spark plug(with a spark plug cleaner or a wire brush)
6. Measure: • Spark plug gap “a”Out of specification  Adjust the spark plug
gap.
7. Install: • Spark plug
TIP
Before installing the spark plug, clean the spark
plug and gasket surface.
8. Install:• Spark plug cap
• Fuel tank
• Air scoop (left/right)
• Seat
• Side cover (left/right)Refer to “GENERAL CHASSIS” on page 5-
1.
EAS2GC1132CHECKING THE IGNITION TIMING
1. Remove:
• Timing mark accessing screw “1”
Manufacturer/model
NGK/CR8E
1
1
2
Spark plug gap 0.7–0.8 mm (0.028–0.031 in)
Spark plug 13 Nm (1.3 m·kgf, 9.4 ft·lbf)
T R..
1

ELECTRICAL SYSTEM
3-41
2. Attach:• Timing light “1”
• Digital tachometer “2”To the high tension code “3”.
3. Adjust: • Engine idling speedRefer to “ADJUSTING THE ENGINE
IDLING SPEED” on page 3-19.
4. Check: • Ignition timingCheck whether the alignment mark “a” on
the left crankcase cover is within the firing
range “b” on the rotor.
Incorrect firing range  Check rotor and
Crankshaft position sensor.
5. Install: • Timing mark accessing screwEAS2GC1133CHECKING AND CHARGING THE BATTERY
Refer to “CHECKING AND CHARGING THE
BATTERY” on page 9-69.
EAS2GC1134REPLACING THE HEADLIGHT BULBEWA
WARNING
Since the headlight bulb gets extremely hot,
keep flammable products and your hands
away from the bulb until it has cooled down.
1. Remove:• Headlight unit bolt “1”
TIP
After you have removed the headlight unit
bolts, lift and remove the headlight unit.
2. Remove:
• Headlight coupler “1”
• Bulb cover “2”
3. Remove: • Headlight bulb “1”
Timing light
90890-03141
Timing light YU-03141
Digital tachometer 90890-06760
Digital tachometer YU-39951-B
Timing mark accessing screw 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
2
1
3
ba
T R..
11
1
2
1

ELECTRICAL SYSTEM
3-42
4. Install:• Headlight bulbFasten the new headlight bulb with the
headlight bulb holder.
ECA
NOTICE
Avoid touching the glass part of the head-
light bulb to keep it free from 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.
5. Install:• Bulb cover
• Headlight coupler
6. Install: • Headlight unit
Headlight unit bolt7 Nm (0.7 m·kgf, 5.1 ft·lbf)
New
T R..

4
TUNING
CHASSIS.......................................................................................................... 4-1
SELECTION OF THE SECONDARY REDUCTION RATIO
(SPROCKET) ............................................................................................ 4-1
DRIVE AND REAR WHEEL SPROCKETS SETTING PARTS .................. 4-1
TIRE PRESSURE............................. .......................................................... 4-1
FRONT FORK SETTING............................................................................ 4-2
CHANGE IN AMOUNT AND CHARACTERISTICS OF FORK OIL............ 4-2
SETTING OF SPRING AFTER REPLACEMENT ...................................... 4-2
FRONT FORK SETTING PARTS............................................................... 4-3
REAR SUSPENSION SETTING ................................................................ 4-3
CHOOSING SET LENGTH ........................................................................ 4-3
SETTING OF SPRING AFTER REPLACEMENT ...................................... 4-4
REAR SHOCK ABSORBER SETT ING PARTS ......................................... 4-4
SUSPENSION SETTING (FRONT FORK)................................................. 4-6
SUSPENSION SETTING (REAR SHOCK ABSORBER) ........................... 4-7

CHASSIS
4-1
EAS2GC1136
CHASSIS
EAS2GC1137SELECTION OF THE SECONDARY REDUC-
TION RATIO (SPROCKET)
reduction ratio>
• It is generally said that the secondary gear ra-tio should be reduced for a longer straight por-
tion of a speed course and should be
increased for a course with many corners. Ac-
tually, however, as the speed depends on the
ground condition of the day of the race, be
sure to run through the circuit to set the ma-
chine suitable for the entire course.
• In actuality, it is very difficult to achieve set- tings suitable for the entire course and some
settings may be sacrificed. Thus, the settings
should be matched to the portion of the
course that has the greatest effect on the race
result. In such a case, run through the entire
course while making notes of lap times to find
the best balance; then, determine the second-
ary reduction ratio.
• If a course has a long straight portion where a machine can run at maximum speed, the ma-
chine is generally set such that it can develop
its maximum revolutions toward the end of the
straight line, with care taken to avoid the en-
gine over-revving.
TIP
Riding technique varies from rider to rider and
the performance of a machine also vary from
machine to machine. Therefore, do not imitate
other rider’s settings from the beginning but
choose your own setting according to the level
of your riding technique.
EAS2GC1138DRIVE AND REAR WHEEL SPROCKETS
SETTING PARTS
EAS2GC1139TIRE PRESSURE
Tire pressure should be adjusted to suit the
road surface condition of the circuit.
• Under a rainy, a muddy, a sandy, or a slippery condition, the tire pressure should be lower
for a larger area of contact with the road sur-
face.
Secondary reduction ratio = Number of
rear wheel sprocket teeth/Number of
drive sprocket teeth
Secondary reduction ratio 3.846 (50/13)
Part name Type Part number
Drive sprocket “1”
(STD) 13T 9383E-13233
Rear wheel
sprocket “2”
48T 5GS-25448-50
(STD) 50T 5TJ-25450-80 52T 5TJ-25452-80
Standard tire pressure 100 kPa (1.00 kgf/cm
2,15 psi)
Extent of adjustment 60–80 kPa (0.60–0.80 kgf/cm
2, 9–
12 psi)

CHASSIS
4-2
• Under a stony or a hard road condition, the tire pressure should be hi gher to prevent a flat
tire.
EAS2GC1140FRONT FORK SETTING
The front fork setting should be made depend-
ing on the rider’s feeli ng of an actual run and
the circuit conditions.
The front fork setting includes the following
three factors:
1. Setting of air spring characteristics • Change the fork oil amount.
2. Setting of spring preload • Change the spring.
3. Setting of damping force
• Change the compression damping force.
• Change the rebound damping force.The spring acts on the load and the damping
force acts on the cushion travel speed.
EAS2GC1141CHANGE IN AMOUNT AND CHARACTERIS-
TICS OF FORK OIL
Damping characteristic near the final stroke
can be changed by changing the fork oil
amount.
EWA
WARNING
Adjust the oil amount in 5 cm3 (0.2 US oz,
0.2 Imp.oz) increments or decrements. Too
small oil amount causes the front fork to
produce a noise at full rebound or the rider
to feel some pressure on his hands or body.
Alternatively, too large oil amount will
cause the air spring characteristics to have
a tendency to be stiffer with the consequent
deteriorated performance and characteris-
tics. Therefore, adjust the front fork within
the specified range.
EAS2GC1142SETTING OF SPRING AFTER REPLACE-
MENT
As the front fork setting can be easily affected
by the rear suspension, take care so that the
front and the rear are balanced (in position etc.)
when setting the front fork.
1. Use of soft spring
• Change the rebound damping force.Turn out one or two clicks.
• Change the compression damping force.
Turn in one or two clicks.
TIP
Generally a soft spring gives a soft riding feel-
ing. Rebound damping tends to become stron-
ger and the front fork may sink deeply over a
series of gaps.
2. Use of stiff spring• Change the rebound damping force.
Turn in one or two clicks.
• Change the compression damping force. Turn out one or two clicks.
Extent of adjustment
100–120 kPa (1.00–1.20 kgf/cm
2,
15–18 psi)
Standard oil amount 345 cm
3 (11.66 US oz, 12.14
lmp.oz)
Extent of adjustment 300–365 cm
3 (10.14–12.34 US
oz, 10.58–12.87 Imp.oz)
A. Air spring characteristics in relation to oil amount change
B. Load
C. Stroke
1. Max. oil amount
2. Standard oil amount
3. Min. oil amount

CHASSIS
4-3
TIP
Generally a stiff spring gives a stiff riding feel-
ing. Rebound damping tends to become weak-
er, resulting in lack of a sense of contact with
the road surface or in a vibrating handlebar.
EAS2GC1143FRONT FORK SETTING PARTS
• Front fork spring “1”
TIP
The I.D. mark (slits) “a” is proved on the end of
the spring.
EAS2GC1144REAR SUSPENSION SETTING
The rear shock absorber setting should be
made depending on the rider’s feeling of an ac-
tual run and the circuit conditions.
The rear suspension setting includes the fol-
lowing two factors:
1. Setting of spring preload • Change the set length of the spring.
• Change the spring.
2. Setting of damping force
• Change the rebound damping force.
• Change the compression damping force.
EAS2GC1145CHOOSING SET LENGTH
1. Place a stand or a block under the engine to put the rear wheel above the floor, and mea-
sure the length “a” between the rear wheel
axle center and the rear fender holding bolt.
2. Remove the stand or block from the engine and, with a rider astride the seat, measure
the sunken length “b” between the rear
wheel axle center and the rear fender hold-
ing bolt.
3. Loosen the locknut “1” and make adjustment by turning the adjuster “2” to achieve the
standard figure from the subtraction of the
length “b” from the length “a”.
Type
Spring
rate N/ mm Part number I.D.
Mark
(slits)
SOFT 4.1 2GB-23141-A0 |||
4.2 2GB-23141-B0 ||||
4.3 2GB-23141-C0 |||||
4.4 2GB-23141-D0 |-|
STD 4.5 2GB-23141-40 —
2GB-23141-E0 |-||
STIFF 4.6 33D-23141-30 |-|||
a
1
Standard figure90–100 mm (3.5–3.9 in)