2013 YAMAHA YZ450F oil level

3-17
CHASSIS
a. Lower level
A. Front
B. Rear
CHECKING THE SPROCKET
1. Inspect:
• Sprocket teeth "a"
Excessive wear→Replace.
Replace the drive sprocket, rear
wheel sprocket and drive chain as a
set.
CHECKING THE DRIVE CHAIN
1. Measure:
• Drive chain length (15 links) "a"
Out of specification→Replace.
• While measuring the drive chain
length, push down on the drive
chain to increase its tension.
• Measure the length between drive
chain roller "1" and "16" as shown.
• Perform this measurement at two or
three different places.
2. Remove:
• Master link clip
•Joint "1"
• Drive chain "2"
3. Clean:
• Drive chain
Place it in kerosene, and brush off
as much dirt as possible. Then re-
move the drive chain from the ker-
osene and dry the drive chain.
4. Check:
• Drive chain stiffness "a"
Clean and oil the drive chain and
hold as illustrated.
Stiff→Replace the drive chain.
5. Install:
• Drive chain "1"
•Joint "2"
• Master link clip "3"
Be sure to install the master link
clip to the direction as shown.
a. Turning direction6. 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". Drive chain length (15
links):
: 242.9 mm
(9.563 in)
Drive chain lubricant:
SAE 10W-40 motor oil
or suitable chain lubri-
cants
Drive chain slack:
50–60 mm (2.0–2.4 in)
To tighten→Turn the adjuster "3"
counterclockwise.
To loosen→Turn the adjuster "3"
clockwise and push wheel for-
ward.

4-31
OIL FILTER ELEMENT AND WATER PUMP
REMOVING THE IMPELLER
SHAFT
1. Remove:
• Impeller "1"
• Washer "2"
• Impeller shaft "3"
Hold the impeller shaft on its width
across the flats "a" with spanners,
etc. and remove the impeller.
REMOVING THE OIL SEAL
It is not necessary to disassemble the
water pump, unless there is an abnor-
mality such as excessive change in
coolant level, discoloration of coolant,
or milky transmission oil.
1. Remove:
• Bearing "1"
• Oil seal "2"CHECKING THE IMPELLER SHAFT
1. Inspect:
• Impeller shaft "1"
Bend/wear/damage→Replace.
Fur deposits→Clean.
CHECKING THE BEARING
1. Inspect:
•Bearing
Rotate inner race with a finger.
Rough spot/seizure→Replace.
CHECKING THE OIL SEAL
1. Inspect:
• Oil seal "1"
Wear/damage→Replace.
INSTALLING THE OIL SEAL
1. Install:
• Oil seal "1"
• Apply the lithium soap base grease
on the oil seal lip.
• Install the oil seal with its manufac-
ture's marks or numbers facing the
right crankcase cover "2".
2. Install:
• Bearing "1"
Install the bearing by pressing its out-
er race parallel.
INSTALLING THE IMPELLER
SHAFT
1. Install:
• Impeller shaft "1"
• Washer "2"
• Impeller "3"
• Take care so that the oil seal lip is
not damaged or the spring does not
slip off its position.
• When installing the impeller shaft,
apply the engine oil on the oil seal
lip, bearing and impeller shaft. And
install the shaft while turning it.
• Hold the impeller shaft on its width
across the flats "a" with spanners,
etc. and install the impeller.
Impeller:
14 Nm (1.4 m•kg, 10
ft•lb)

5-14
FRONT BRAKE AND REAR BRAKE
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake caliper.
2. Install:
• Brake hose holder "1"
• Bolt (brake hose holder) "2"
Align the top "a" of the brake hose
holder with the paint "b" of the brake
hose.
3. Pass the brake hose through the
cable guide "1".
4. Install:
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Always use new copper washers.
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake master cylinder.
INSTALLING THE REAR BRAKE
HOSE
1. Install:
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Always use new copper washers.
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake caliper.
2. Install:
• Brake hose holder "1"
• Screw (brake hose holder) "2"
After installing the brake hose
holders, make sure the brake hose
does not contact the spring (rear
shock absorber). If it does, correct
its twist.
FILLING THE BRAKE FLUID
1. Fill:
• Brake fluid
Until the fluid level reaches
"LOWER" level line "a".
• Use only the designated quality
brake fluid:
otherwise, the rubber seals may
deteriorate, causing leakage and
poor brake performance.
• Refill with the same type of brake
fluid;
mixing fluids may result in a
harmful chemical reaction and
lead to poor performance.
• Be careful that water does not
enter the master cylinder when
refilling. Water will significantly
lower the boiling point of the flu-
id and may result in vapor lock.
Bolt (brake hose holder):
8 Nm (0.8 m•kg, 5.8 ft
•lb)
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Screw (brake hose hold-
er):
3 Nm (0.3 m•kg, 2.2
ft•lb)
Recommended brake flu-
id:
DOT #4

5-20
FRONT FORK
5. Measure:
• Oil level (left and right) "a"
Out of specification → Adjust.
6. Tighten:
• Locknut "1"
Fully finger tighten the locknut onto
the damper assembly.
7. Loosen:
• Compression damping adjuster
"1"
• Loosen the compression damping
adjuster finger tight.
• Record the set position of the ad-
juster (the amount of turning out the
fully turned in position).
8. Install:
• Base valve "1"
To damper assembly "2".
First bring the damper rod pressure to
a maximum. Then install the base
valve while releasing the damper rod
pressure.
9. Check:
• Damper assembly
Not fully stretched → Repeat the
steps 2 to 8.
10. Tighten:
• Base valve "1"
Hold the damper assembly with the
cap bolt ring wrench "2" and use the
cap bolt wrench "3" to tighten the
base valve with specified torque.
11. After filling, pump the damper as-
sembly "1" slowly up and down
more than 10 times to distribute
the fork oil.12. While protecting the damper as-
sembly "1" with a rag and com-
pressing fully, allow excessive oil
to overflow on the base valve
side.
Take care not to damage the damp-
er assembly.
13. Allow the overflowing oil to es-
cape at the hole "a" in the damper
assembly.
The overflow measures about 8
cm3(0.28 Imp oz, 0.27 US oz).
14. Check:
• Damper assembly smooth move-
ment
Tightness/binding/rough spots →
Repeat the steps 2 to 13. Standard oil level:
145–148 mm (5.71–5.83
in)
From top of fully
stretched damper as-
sembly.
Base valve:
29 Nm (2.9 m•kg, 21 ft•
lb)
Cap bolt wrench:
YM-01500/90890-01500
Cap bolt ring wrench:
YM-01501/90890-01501

7-11
FUEL INJECTION SYSTEM
SENSOR OPERATION TABLE
Diagnos-
tic code
No.ItemActuation or
displayChecking methodActuation or LCD standard display
values
D01 Throttle angle DisplayDisplays the throttle angle. 0–125°
Check with throttle fully closed. When throttle is fully closed:15–19°
Check with throttle fully open. When throttle is fully opened:95–
101 °
D02 Atmosphere DisplayDisplays the atmospheric pres-
sure.
• Measure the atmospheric pres-
sure.0–126 kPa
Displays the atmospheric pressure
according to the elevation and
weather.
Example
0 m above sea level: Approx: 101
kPa
3000 m above sea level:Approx: 70
kPa
D03 Intake air pressure DisplayDisplays the intake air pressure.
• Check the intake manifold pres-
sure.
• Check that the intake air pres-
sure changes while the engine is
being cranked.0–126 kPa
While the engine is stopped: Dis-
plays the atmospheric pressure ac-
cording to the elevation and
weather.
Example
0 m above sea level: Approx: 101
kPa
3000 m above sea level:Approx: 70
kPa
While the engine is being cranked:
Displays the intake air pressure.
D05 Intake air temperature DisplayDisplays the intake air tempera-
ture.
• Check the temperature in the in-
take manifold.-20–100°C
Cold engine: Displayed tempera-
ture is close to the ambient temper-
ature.
Warm engine: Displayed tempera-
ture is approximately 20 °C higher
than the ambient temperature.
D06 Coolant temperature DisplayDisplays the coolant temperature.
• Check the coolant temperature.-20–150°C
Cold engine: Displayed tempera-
ture is close to the ambient temper-
ature.
Warm engine: Displayed tempera-
ture is the current coolant tempera-
ture.
D08 Lean angle sensor DisplayDisplays the lean angle sensor
output voltage.
Remove the ECU and incline it 45°
or more.0–5.0 V
1.0 V: Upright
4.0 V: Overturned
D30 Ignition coil ActuationCheck that power is supplied to
the ignition coil.
• Check that a spark is generated.
• Illuminates the engine trouble
warning light.Actuates the ignition coil for five
times every second.
The "WARNING" LED on the FI di-
agnostic tool comes on each time
the fuel injector is actuated.

8-1
CHASSIS
TUNING
CHASSIS
SELECTION OF THE SECONDARY
REDUCTION RATIO (SPROCKET)
ondary gear reduction ratio>
• It is generally said that the second-ary gear ratio should be reduced for
a longer straight portion of a speed
course and should be increased for
a course with many corners. Actual-
ly, 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 machine suit-
able for the entire course.
• In actuality, it is very difficult to achieve settings suitable for the en-
tire course and some settings may
be sacrificed. Thus, the settings
should be matched to the portion of
the course that has the greatest ef-
fect 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, deter-
mine the secondary reduction ratio.
• If a course has a long straight por- tion where a machine can run at
maximum speed, the machine is
generally set such that it can devel-
op its maximum revolutions toward
the end of the straight line, with care
taken to avoid the engine over-rev-
ving.
Riding technique varies from rider to
rider and the performance of a ma-
chine also vary fr om machine to ma-
chine. Therefore, do not imitate other
rider's settings from the beginning but
choose your own setting according to
the level of your riding technique.
DRIVE AND REAR WHEEL
SPROCKETS SETTING PARTS
TIRE PRESSURE
Tire pressure should be adjust to suit
the road surface condition of the cir-
cuit.
• Under a rainy, muddy, sandy, or slippery condition, the tire pressure
should be lower for a larger area of
contact with the road surface.
• Under a stony or hard road condi- tion, the tire pressure should be
higher to prevent a flat tire. FRONT FORK SETTING
The front fork setting should be made
depending on the rider's feeling of an
actual run and the circuit conditions.
The front fork setting includes the fol-
lowing three factors:
1. Setting of air spring characteris-
tics
• Change the fork oil amount.
2. Setting of spring preload
• Change the spring.
3. Setting of damping force • Change the compression damp-
ing.
• Change the rebound damping. The spring acts on the load and
the damping force acts on the
cushion travel speed.
CHANGE IN AMOUNT AND
CHARACTERISTICS OF FORK OIL
Damping characteristic near the final
stroke can be changed by changing
the fork oil amount.
Adjust the oil amount in 5 cm3 (0.2
Imp oz, 0.2 US 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
characteristics. Therefore, adjust
the front fork within the specified
range.
Secondary reduction ratio = Number of rear wheel sprocket
teeth/Number of drive sprocket
teeth
Standard secondary
reduction ratio 3.692
(48/13)
* 3.769
(49/13)
* Except for USA and CDN
Part name Size Part number
Drive
sprocket "1" (STD) 13T 9383E-13233
Rear wheel
sprocket "2" 47T 17D-25447-50
(STD) 48T 17D-25448-50
* (STD) 49T 17D-25449-50 50T 17D-25450-50
51T 17D-25451-50
52T 17D-25452-50
* Except for USA and CDN
Standard tire pressure:100 kPa (1.0 kgf/cm
2,
15 psi)
Extent of adjustment: 60–80 kPa (0.6–0.8 kgf/
cm
2, 9.0–12 psi)
Extent of adjustment: 100–120 kPa (1.0–1.2
kgf/cm
2, 15–18 psi)
Standard oil amount:
355 cm3 (12.5 Imp oz,
12.0 US oz)
Extent of adjustment:
300–365 cm
3 (10.6–12.8
Imp oz, 10.1–12.3 US
oz)