2016 YAMAHA WR 450F engine

GENERAL CHASSIS
5-1
EAS2GC1150
TIP
This section is intended for those who have basic knowledge and skill concerning the servicing of
Yamaha motorcycles (e.g., Yamaha dealers, serv ice engineers, etc.). Those who have little knowl-
edge and skill concerning servicing are requested not to undertake inspection, adjustment, disas-
sembly, or reassembly only by reference to this manual. It may lead to servicing trouble and
mechanical damage.
EAS2GC1151
GENERAL CHASSIS
Removing the seat and side cover
OrderPart name Q’tyRemarks
1 Seat 1
2 Air scoop (left) 1
3 Air scoop (right) 1
4 Side cover (left) 1
5 Side cover (right) 1
6 Rear fender 1
For installation, reverse the removal proce-
dure.
4
(2)
65
1
3
2
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
22 Nm (2.2 m kgf, 16 ft Ibf)T.R.
1.3 Nm (0.13 m kgf, 0.94 ft Ibf)T.R.16 Nm (1.6 m kgf, 12 ft Ibf)T.R.

HANDLEBAR
5-33
EAS2GC1193
HANDLEBAR
Removing the handlebar
OrderPart name Q’tyRemarks
1 Clutch cable 1 Disconnect.
2 Clutch switch 1
3 Clutch lever holder 1
4 Engine stop switch 1
5 Brake master cylinder 1
6 Throttle cable cap 1
7 Throttle cable (pull) 1 Disconnect.
8 Throttle cable (return) 1 Disconnect.
9 Right grip 1
10 Tube guide 1
11 Start switch 1
12 Left grip 1
13 Handlebar upper holder 2
14 Handlebar 1

HANDLEBAR
5-37
5. Install:• Engine stop switch “1”
• Clutch lever “2”
• Clutch lever holder “3”
•Clamp “4”
TIP
• The engine stop switch, the clutch lever, and the clutch lever holder should be installed ac-
cording to the dimensions shown.
• Pass the engine stop switch lead through the
middle of the clutch lever holder.
6. Install: • Right grip “1”
• Collar “2”Apply adhesive to the tube guide “3”.
TIP
• Before applying the adhesive, wipe off grease or oil on the tube guide surface “a” with a lac-
quer thinner.
• Install the grip to the tube guide so that the grip match mark “b” and tube guide slot “c”
form the angle as shown. 7. Install:
• Rubber cover “1”
• Throttle grip “2”
TIP
Apply the lithium-soap-based grease on the
throttle grip sliding surface.
8. Install:• Throttle cables “1”
TIP
Slightly coat the end of throttle cable and inside
of throttle grip with lithium-soap-based grease.
Then, mount the throttle grip onto the handle-
bar.
9. Install:
• Throttle cable housings “1”
• Screw (throttle cable housings) “2”
EWA
Engine stop switch screw0.5 Nm (0.05 m·kgf, 0.36 ft·lbf)
Clutch lever holder bolt 3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
T R..
Screw (throttle cable housings)3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
64
1 b
c
3
64
T R..

CHAIN DRIVE
5-68
EAS2GC1221
CHAIN DRIVE
Removing the drive chain
Job OrderPart name Q’tyServicing Information
Drive sprocket Refer to “ENGINE REMOVAL” on page 6-1.
1 Drive chain 1
For installation, reverse the removal proce-
dure.
1
T.R.75 Nm (7.5 mlbf)
kgf, 54 ft
T.R.7 Nm (0.7 mlbf)
kgf, 5.1 ft

CHAIN DRIVE
5-71
c. After riveting, make sure the space “c”, which is inside of the connecting link “3” and
inside of the connecting plate “1”, is 14.1–
14.3 mm (0.56–0.65 in).
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Lubricate:
•Drive chain
3. Install: • Drive sprocket
• Lock washer
• Drive sprocket nutRefer to “ENGINE REMOVAL” on page 6-1.
ECA
NOTICE
Never install a new drive chain onto worn
drive chain sprockets; this will dramatically
shorten the drive chain’s life.
4. Adjust:• Drive chain slackRefer to “ADJUSTING THE DRIVE CHAIN
SLACK” on page 3-31.
ECA
NOTICE
A drive chain that is too tight will overload
the engine and other vital parts, and one
that is too loose can skip and damage the
swingarm or cause an accident. Therefore,
keep the drive chain slack within the speci-
fied limits.
Recommended lubricant Chain lubricant suitable for O-
ring chains
Drive sprocket nut 75 Nm (7.5 m·kgf, 54 ft·lbf)
Drive chain slack (on a suitable
stand) 50.0–60.0 mm (1.97–2.36 in)
New
T R..

6
ENGINE
ENGINE REMOVAL......................................................................................... 6-1
REMOVING THE SILENCER ..................................................................... 6-6
REMOVING THE EXHAUST PIPE 2.......................................................... 6-6
REMOVING THE DRIVE SPROCKET ....................................................... 6-6
REMOVING THE ENGINE ......................................................................... 6-7
CLEANING THE SPARK ARRESTER ....................................................... 6-7
CHECKING THE SILENCER AND EXHAUST PIPE.................................. 6-8
INSTALLING THE ENGINE........................................................................ 6-8
INSTALLING THE BRAKE PEDAL ............................................................ 6-9
INSTALLING THE DRIVE SPROCKET...................................................... 6-9
INSTALLING THE EXHAUST PIPE AND MUFFLER................................. 6-9
CAMSHAFT .................................................................................................... 6-11
REMOVING THE CAMSHAFT ................................................................. 6-13
CHECKING THE CAMSHAFT.................................................................. 6-14
CHECKING THE TIMING CHAIN AND CAMSHAFT SPROCKET .......... 6-15
CHECKING THE TIMING CHAIN TENSIONERS .................................... 6-15
CHECKING THE DECOMPRESSION SYSTEM.............. ........................ 6-16
INSTALLING THE CAMSHAFTS ............................................................. 6-16
CYLINDER HEAD ........................................................................................... 6-18
REMOVING THE CYLINDER HEAD........................................................ 6-20
CHECKING THE TIMING CHAIN GUIDE (INTAKE SIDE) ...................... 6-20
CHECKING THE CYLINDER HEAD ........................................................ 6-20
INSTALLING THE CYLINDER HEAD ...................................................... 6-21
VALVES AND VALVE SPRINGS ................................................................... 6-23
REMOVING THE VALVES ....................................................................... 6-24
CHECKING THE VALVES AND VALVE GUIDES ................................... 6-25
CHECKING THE VALVE SEATS ............................................................. 6-26
CHECKING THE VALVE SPRINGS......................................................... 6-28
CHECKING THE VALVE LIFTERS .......................................................... 6-29
INSTALLING THE VALVES ..................................................................... 6-29
CYLINDER AND PISTON ............................................................................... 6-31
REMOVING THE PISTON ....................................................................... 6-32
CHECKING THE CYLINDER AND PISTON ............................................ 6-32
CHECKING THE PISTON RINGS............................................................ 6-33
CHECKING THE PISTON PIN ................................................................. 6-34
INSTALLING THE PISTON AND CYLINDER .......................................... 6-34
ELECTRIC STARTER .................................................................................... 6-36
CHECKING THE STARTER MOTOR ...................................................... 6-38
ASSEMBLING THE STARTER MOTOR .................................................. 6-39

ENGINE REMOVAL
6-1
EAS2GC1225
TIP
This section is intended for those who have basic knowledge and skill concerning the servicing of
Yamaha motorcycles (e.g., Yamaha dealers, serv ice engineers, etc.). Those who have little knowl-
edge and skill concerning servicing are requested not to undertake inspection, adjustment, disas-
sembly, or reassembly only by reference to this manual. It may lead to servicing trouble and
mechanical damage.
EAS2GC1226
ENGINE REMOVAL
Removing the exhaust pipe
OrderPart name Q’tyRemarks
Refer to “INSTALLING THE EXHAUST
PIPE AND MUFFLER” on page 6-9.
Side cover (right) Refer to “GENERAL CHASSIS” on page 5-1.
Rear shock absorber assembly lower bolt Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-58.
Connecting arm bolt (relay arm side) Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-58.
Starter motor Refer to “ELECTRIC STARTER” on page 6-
36.
1 Silencer clamp 1 Loosen.
2 Silencer 1
3 Exhaust pipe 2 clamp 1 Loosen.
105
9
26
1 6 6
3
8 4
7
(4)
(6)
30 Nm (3.0 m kgf, 22 ft Ibf)T
.R.
30 Nm (3.0 m kgf, 22 ft Ibf)T.R.
New
New
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.
12 Nm (1.2 m kgf, 8.7 ft Ibf)T.R.12 Nm (1.2 m kgf, 8.7 ft Ibf)T.R.
20 Nm (2.0 m kgf, 14 ft Ibf)T.R.New
LT
LT
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.9 Nm (0.9 m kgf, 6.5 ft Ibf)T .R.
5 Nm (0.5 m kgf, 3.6 ft Ibf)T.R.
T
.R.*kgf
7 Nm (0.7 m , 5.1 ft lbf)
10 Nm (1.0 m kgf, 7.2 ft Ibf)
*

ENGINE REMOVAL
6-2
4 Exhaust pipe 21
5 Exhaust pipe 1 1
6 Gaskets 3
7 Exhaust pipe 1 protector 1
8 Exhaust pipe 2 protector 1
9 Silencer cap 1
10 Spark arrester 1
For installation, reverse the removal proce-
dure.
Removing the exhaust pipe
Order Part name Q’tyRemarks
105
9
26
1 6 6
3
8 4
7
(4)
(6)
30 Nm (3.0 m kgf, 22 ft Ibf)T
.R.
30 Nm (3.0 m kgf, 22 ft Ibf)T.R.
New
New
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.
12 Nm (1.2 m kgf, 8.7 ft Ibf)T.R.12 Nm (1.2 m kgf, 8.7 ft Ibf)T.R.
20 Nm (2.0 m kgf, 14 ft Ibf)T.R.New
LT
LT
10 Nm (1.0 m kgf, 7.2 ft Ibf)T.R.9 Nm (0.9 m kgf, 6.5 ft Ibf)T .R.
5 Nm (0.5 m kgf, 3.6 ft Ibf)T.R.
T
.R.*kgf
7 Nm (0.7 m , 5.1 ft lbf)
10 Nm (1.0 m kgf, 7.2 ft Ibf)