2011 YAMAHA YZ450F seat adjustment

CONTENTS
CHAPTER 1
GENERAL
INFORMATION
LOCATION OF
IMPORTANT LABELS ..... 1-1
DESCRIPTION ................. 1-5
CONSUMER
INFORMATION................. 1-6
FEATURES....................... 1-7
INCLUDED PARTS .......... 1-9
IMPORTANT
INFORMATION................. 1-9
HANDLING THE
ELECTRONIC PARTS ... 1-10
CHECKING OF
CONNECTION ................ 1-10
SPECIAL TOOLS ........... 1-12
CONTROL
FUNCTIONS ................... 1-17
STARTING
AND BREAK-IN.............. 1-17
TORQUE-CHECK
POINTS........................... 1-19
CLEANING
AND STORAGE ............. 1-20
CHAPTER 2
SPECIFICATIONS
GENERAL
SPECIFICATIONS ............ 2-1
MAINTENANCE
SPECIFICATIONS ............ 2-3
TIGHTENING
TORQUES ...................... 2-11
LUBRICATION
DIAGRAMS .................... 2-17
CABLE ROUTING
DIAGRAM ....................... 2-18
CHAPTER 3
REGULAR
INSPECTION AND
ADJUSTMENTS
MAINTENANCE
INTERVALS ...................... 3-1
PRE-OPERATION
INSPECTION
AND MAINTENANCE ....... 3-5
ENGINE ............................ 3-6
CHASSIS ........................ 3-14
ELECTRICAL ................. 3-24
CHAPTER 4
ENGINE
SEAT
AND SIDE COVERS ......... 4-1
EXHAUST PIPE
AND SILENCER ............... 4-3
RADIATOR ....................... 4-7
CAMSHAFTS.................. 4-10
CYLINDER HEAD........... 4-15
VALVES AND
VALVE SPRINGS ........... 4-19
CYLINDER
AND PISTON .................. 4-23
CLUTCH ......................... 4-27
OIL FILTER ELEMENT
AND WATER PUMP ....... 4-31
BALANCER .................... 4-35
OIL PUMP ....................... 4-37
KICK SHAFT
AND SHIFT SHAFT ........ 4-40
AC MAGNETO................ 4-45
ENGINE REMOVAL ....... 4-47
CRANKCASE
AND CRANKSHAFT ...... 4-52
TRANSMISSION,
SHIFT CAM
AND SHIFT FORK .......... 4-58
CHAPTER 5
CHASSIS
FRONT WHEEL
AND REAR WHEEL .........5-1
FRONT BRAKE
AND REAR BRAKE..........5-6
FRONT FORK .................5-16
HANDLEBAR..................5-24
STEERING ......................5-28
SWINGARM ....................5-32
REAR
SHOCK ABSORBER ......5-37
CHAPTER 6
FUEL SYSTEM
FUEL TANK ......................6-1
THROTTLE BODY ............6-4
CHAPTER 7
ELECTRICAL
ELECTRICAL
COMPONENTS AND
WIRING DIAGRAM ...........7-1
IGNITION SYSTEM...........7-3
THROTTLE POSITION
SENSOR SYSTEM ...........7-6
FUEL INJECTION
SYSTEM............................7-9
FUEL PUMP SYSTEM ....7-35
ELECTRICAL
COMPONENTS...............7-36
CHAPTER 8
TUNING
CHASSIS ..........................8-1

2-4
MAINTENANCE SPECIFICATIONS
Timing chain:
Timing chain type/No. of links 98XRH2010-122M/122 ----
Timing chain adjustment method Automatic ----
Valve, valve seat, valve guide:
Valve clearance (cold)
IN 0.10–0.15 mm (0.0039–0.0059 in) ----
EX 0.20–0.25 mm (0.0079–0.0098 in) ----
Valve dimensions:
"A" head diameter (IN) 35.9–36.1 mm (1.4134–1.4213 in) ----
"A" head diameter (EX) 29.9–30.1 mm (1.1772–1.1850 in) ----
"B" face width (IN) 2.26 mm (0.089 in) ----
"B" face width (EX) 2.26 mm (0.089 in) ----
"C" seat width (IN) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)
"C" seat width (EX) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)
"D" margin thickness (IN) 1.3 mm (0.0512 in) ----
"D" margin thickness (EX) 1.0 mm (0.0394 in) ----
Stem outside diameter (IN) 5.475–5.490 mm (0.2156–0.2161 in) 5.445 mm
(0.2144 in)
Stem outside diameter (EX) 5.465–5.480 mm (0.2152–0.2157 in) 5.435 mm
(0.2140 in)
Guide inside diameter (IN) 5.500–5.512 mm (0.2165–0.2170 in) 5.550 mm
(0.2185 in)
Guide inside diameter (EX) 5.500–5.512 mm (0.2165–0.2170 in) 5.550 mm
(0.2185 in) Item Standard Limit

3-1
MAINTENANCE INTERVALS
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
• The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind that such factors as
weather, terrain, geographical location, and individual usage will alter the required maintenance and lubrication intervals.
If you are a doubt as to what intervals to follow in maintaining and lubricating your machine, consult your Yamaha dealer.
• Periodic inspection is essential in making full use of the machine performance. The service life of the parts varies sub-
stantially according to the environment in which the machine runs (e.g., rain, dirt, etc.). Therefore, earlier inspection is
required by reference to the list below..
ItemAfter
break-
inEvery
race
(about
2.5
hours)
Every
third
(about
7.5
hours)Every
fifth
(about
12.5
hours)
As re-
quiredRemarks
ENGINE OIL
Replace●●
VALVES
Check the valve clearances●●The engine must be cold.
Inspect●Check the valve seats and valve
stems for wear.
Replace●
VALVE SPRINGS
Inspect●Check the free length and the tilt.
Replace●
VALVE LIFTERS
Inspect●Check for scratches and wear.
Replace●
CAMSHAFTS Inspect the camshaft surface.
Inspect●Inspect the decompression system.
Replace●
CAMSHAFT SPROCKETS
Inspect●Check for wear on the teeth and for
damage.
Replace●
PISTON
Inspect●Inspect crack.
Clean●Inspect carbon deposits and eliminate
them.
Replace●●Replace the piston, piston pin, piston
pin clip, and piston ring all as a set.
PISTON RING
Inspect●Check ring end gap.
Replace●●Replace the piston, piston pin, piston
pin clip, and piston ring all as a set.
PISTON PIN
Inspect●
Replace●●Replace the piston, piston pin, piston
pin clip, and piston ring all as a set.
3

3-8
ENGINE
ADJUSTING THE THROTTLE
CABLE FREE PLAY
1. Check:• Throttle grip free play "a"
Out of specification →Adjust.
2. Adjust: • Throttle grip free play
Throttle grip free play adjustment
steps:
a. Slide the adjuster cover.
b. Loosen the locknut "1".
c. Turn the adjuster "2" until the specified free play is obtained.
d. Tighten the locknut.
Before adjusting the throttle cable
free play, the engine idle speed
should be adjusted.
After adjusting th e throttle cable
free play, start the engine and turn
the handlebar to right and left and
make sure that the engine idling
does not run faster.
LUBRICATING THE THROTTLE
1. Remove: • Cover (throttle cable cap) "1"
• Cover (grip cap) "2"
• Throttle grip cap "3" 2. Apply:
• Lithium soap base greaseOn the throttle cable end "a".
3. Install: • Throttle grip cap
• Screw (throttle grip cap)
• Cover (grip cap)
• Cover (throttle cable cap)
CHECKING THE THROTTLE
VALVE PULLY COVER DRAIN
HOSE
Drain the water that stays in the throt-
tle valve pulley cove r after a machine
wash or a rainy weather ride.
1. Drain the water by picking up the flat portion of the lower end "a" of
the drain hose.
CLEANING THE AIR FILTER
ELEMENT
1. Remove: •Seat
2. Remove the fuel tank bolt (front) "1" and lift the fuel tank.
Hold the fuel tank in position by the
use of the fuel tank holding cable "2".
3. Remove:• Mounting bolt for air filter case
cover 4. Loosen and release the binder "1"
and lift the air filter case lid.
Hold the air filter case lid by the use of
the binder.
5. Remove:• Air filter guide
• Air filter element "1"
Do not remove the thin sheet (air
filter element 2) "2" under the air
filter element unless it is dirty. It is
there to prevent foreign matter
from dropping in to the throttle
body. If the thin sheet must be re-
moved for cleaning, lift it carefully
to avoid loosening the dirt, and
then temporarily block the throttle
body opening with a clean, lint-free
cloth.
6. Clean: • Air filter element
Clean them with solvent.
After cleaning, remo ve the remaining
solvent by squeezing the element.
• Do not twist the element when squeezing the element.
• Leaving too much of solvent in
the element may result in poor
starting.
7. Inspect:• Air filter elementDamage → Replace.
Throttle grip free play
"a":
3–5 mm (0.12–0.20 in)
Screw (throttle grip cap): 4 Nm (0.4 m•kg, 2.9
ft•lb)

3-11
ENGINE
3. Adjust:• Engine idling speed
Adjustment steps:
a. Turn the starter knob/idle screw "1" until the specified engine idling
speed is obtained.
Using the digital tachometer, mea-
sure the engine speed with the detec-
tor "c" pinched in the high tension
cord "2" of the ignition coil.
ADJUSTING THE VALVE
CLEARANCE
• This section is intended for those who have basic knowledge and skill
concerning the servicing of Yama-
ha motorcycles (e.g., Yamaha deal-
ers, service engineers, etc.) Those
who have little knowledge and skill
concerning servicing are requested
not to undertake in spection, adjust-
ment, disassembly, or reassembly
only by reference to this manual. It
may lead to servicing trouble and
mechanical damage.
• The valve clearance should be ad- justed when the engine is cool to
the touch.
1. Remove:•Seat
Refer to "SEAT AND SIDE COV-
ERS" section in the CHAPTER 4.
•Fuel tank
Refer to "FUEL TANK" section in
the CHAPTER 6.
2. Remove:
• Spark plug
• Cylinder head coverRefer to "CAMSHAFTS" section
in the CHAPTER 4.
3. Remove: • Timing mark accessing screw "1"
• Crankshaft end accessing screw "2"
• O-ring
4. Check: • Valve clearanceOut of specification →Adjust.
Checking steps:
a. Turn the crankshaft counterclock-
wise with a wrench.
b. Align the alignment mark "a" on the rotor with the alignment mark
"b" on the crankcase cover.
Make sure that the alignment mark
"c" on the exhaust camshaft sprocket
and the alignment mark "d" on the in-
take camshaft sprocket are aligned
with the edge of the cylinder head.
c. Measure the valve clearance "e" using a feeler gauge "1".
Record the measured reading if the
clearance is incorrect.
Digital tachometer:
YU-39951-B/90890-
06760
To increase the engine idling speed →Turn the starter
(choke) knob/idling screw
counterclockwise "a".
To decrease the engine idling
speed →Turn the starter
(choke) knob/idling screw
clockwise "b".
Engine idling speed:1,900–2,100 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)

4-1
SEAT AND SIDE COVERS
ENGINE
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request-
ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.
SEAT AND SIDE COVERS
REMOVING THE SEAT AND SIDE COVERS
Order Part name Q'ty Remarks1Seat 1
2 Air scoop (left) 1
3 Air scoop (right) 1
4 Side cover (left) 1
5 Side cover (right) 1
6 Number plate 1 Refer to removal section.
7 Rear fender 1

6-1
FUEL TANK
FUEL SYSTEM
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request-
ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.
FUEL TANK
REMOVING THE FUEL TANK
Order Part name Q'ty Remarks
SeatRefer to "SEAT AND SIDE COVERS" section
in the chapter 4.
Air scoop (left/right) 1/1Refer to "SEAT AND SIDE COVERS" section
in the chapter 4.
1 Fuel pump coupler 1 Disconnect.
2 Fuel hose 1 Refer to removal section.
3 Fuel tank bolt 2
4 Fuel tank 1 Refer to removal section.
5 Fuel pump bracket 1
6 Fuel pump assembly 1 Refer to removal section.
7O-ring 1
6

8-2
CHASSIS
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
SETTING OF SPRING AFTER
REPLACEMENT
As the front fork setting can be easily
affected by rear suspension, take
care so that the machine front and
rear are balanced (in position, etc.)
when setting the front fork.
1. Use of soft spring
• Change the rebound damping.
Turn out one or two clicks.
• Change the compression damp-
ing.
Turn in one or two clicks.
Generally a soft spring gives a soft
riding feeling. Rebound damping
tends to become stronger and the
front fork may sink deeply over a se-
ries of gaps.
2. Use of stiff spring
• Change the rebound damping.
Turn in one or two clicks.
• Change the compression damp-
ing.
Turn out one or two clicks.
Generally a stiff spring gives a stiff
riding feeling. Rebound damping
tends to become weaker, resulting in
lack of a sense of contact with the
road surface or in a vibrating handle-
bar.
FRONT FORK SETTING PARTS
• Front fork spring "1"
The I.D. mark (slits) "a" is proved on
the end of the spring.
REAR SUSPENSION SETTING
The rear suspension setting should
be made depending on the rider's
feeling of an actual run and the circuit
conditions.
The rear suspension setting includes
the following 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.
• Change the compression damp-
ing.CHOOSING SET LENGTH
1. Place a stand or block under the
engine to put the rear wheel
above the floor, and measure 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
holding bolt.
3. Loosen the locknut "1" and make
adjustment by turning the spring
adjuster "2" to achieve the stan-
dard figure from the subtraction of
the length "b" from the length "a".
• If the machine is new and after it is
broken in, the same set length of
the spring may change because of
the initial fatigue, etc. of the spring.
Therefore, be sure to make reeval-
uation.
• If the standard figure cannot be
achieved by adjusting the spring
adjuster and changing the spring
set length, replace the spring with
an optional one and make readjust-
ment.
TY
PESPRIN
G
RATESPRING PART
NUMBERI.D.
MA
RK
(slit
s)
SO
FT0.459 33D-23141-20 |-||
ST
D0.46933D-23141-30 |-|||
33D-23141-D0—
STI
FF0.479 33D-23141-40 |-||||
Standard figure:
90–100 mm (3.5–3.9 in)
8