2011 YAMAHA WR 450F engine

2-12
TIGHTENING TORQUES
TIGHTENING TORQUES
ENGINE
△- marked portion shall be checked for torque tightening after break-in or before each race.
*1: Tighten the cylinder head bolts to 30 Nm (3.0 m•kg, 22 ft•lb) in the proper tightening sequence, remove and retighten
the cylinder head bolts to 20 Nm (2.0 m•kg, 14 ft•lb) in the proper tightening sequence, and then tighten the cylinder head
bolts further to reach the specified angle 180° in the proper tightening sequence.
Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb
Spark plug M10S × 1.0 1 13 1.3 9.4
Camshaft cap M6 × 1.0 10 10 1.0 7.2
Cylinder head blind plug screw M12 × 1.0 1 28 2.8 20
Cylinder head (stud bolt) M8 × 1.25 1 15 1.5 11
Cylinder head (bolt) M10 × 1.25 4 Refer to TIP.*1
Cylinder head (bolt) M6 × 1.0 2 10 1.0 7.2
Cylinder head cover M6 × 1.0 2 10 1.0 7.2
Cylinder M6 × 1.0 1 10 1.0 7.2
Timing chain tensioner M6 × 1.0 2 10 1.0 7.2
Timing chain tensioner cap bolt M6 × 1.0 1 7 0.7 5.1
Timing chain guide (intake side) M6 × 1.0 2 10 1.0 7.2
Exhaust pipe (nut) M8 × 1.25 1 20 2.0 14
Exhaust pipe (bolt) M8 × 1.25 1 20 2.0 14
△Silencer M8 × 1.25 2 30 3.0 22
Silencer clamp M8 × 1.25 1 16 1.6 11
Exhaust pipe protector M6 × 1.0 3 10 1.0 7.2
Spark arrester M5 × 0.8 4 7 0.7 5.1
Silencer cap M5 × 0.8 6 5 0.5 3.6
Air induction pipe M6 × 1.0 2 10 1.0 7.2
Air cut-off valve assembly and bracket M6 × 1.0 2 10 1.0 7.2
Bracket (air cut-off valve) and frame M6 × 1.0 2 7 0.7 5.1
Carburetor joint M6 × 1.0 3 10 1.0 7.2
Carburetor joint clamp M4 × 0.7 1 3 0.3 2.2
△Air filter case M6 × 1.0 2 8 0.8 5.8
Air filter joint clamp M6 × 1.0 1 3 0.3 2.2
Air filter joint and air filter case M5 × 0.8 1 4 0.4 2.9
Throttle cable adjust bolt and locknut M6 × 0.75 1 4 0.4 2.9
Throttle cable (pull) M6 × 1.0 1 4 0.4 2.9
Throttle cable (return) M12 × 1.0 1 11 1.1 8.0
Throttle cable cover M5 × 0.8 2 4 0.4 2.9
Hot starter plunger M12 × 1.0 1 2 0.2 1.4
Hot starter cable adjust bolt and locknut M6 × 0.75 1 4 0.4 2.9
Air filter element M6 × 1.0 1 2 0.2 1.4
Radiator stay M6 × 1.0 6 7 0.7 5.1
Radiator M6 × 1.0 4 10 1.0 7.2
Radiator hose clamp M6 × 1.0 8 2 0.2 1.4

2-13
TIGHTENING TORQUES
Radiator pipe 1, 2 M10 × 1.0 2 10 1.0 7.2
Impeller M8 × 1.25 1 14 1.4 10
Water pump housing cover M6 × 1.0 3 10 1.0 7.2
Coolant drain bolt M6 × 1.0 1 10 1.0 7.2
Oil pump cover M4 × 0.7 1 2 0.2 1.4
Oil pump M6 × 1.0 2 10 1.0 7.2
Oil pump drive gear shaft M6 × 1.0 1 10 1.0 7.2
Engine oil drain bolt (oil filter) M6 × 1.0 1 10 1.0 7.2
Oil filter cover M6 × 1.0 2 10 1.0 7.2
Oil check bolt (cylinder head) M6 × 1.0 1 10 1.0 7.2
△Oil hose clamp — 2 2 0.2 1.4
Crankshaft end accessing screw M27 × 1.5 1 10 1.0 7.2
Timing mark accessing screw M14 × 1.5 1 6 0.6 4.3
Clutch cover M6 × 1.0 7 10 1.0 7.2
Crankcase cover (right) M6 × 1.0 8 10 1.0 7.2
Crankcase cover (right) M6 × 1.0 2 12 1.2 8.7
Crankcase cover (left) M6 × 1.0 8 10 1.0 7.2
Idle gear cover (starter motor) M6 × 1.0 2 10 1.0 7.2
Crankcase M6 × 1.0 12 12 1.2 8.7
Clutch cable holder M6 × 1.0 1 10 1.0 7.2
Oil drain bolt (crankcase right) M6 × 1.25 1 20 2.0 14
Oil drain bolt (crankcase left) M6 × 1.0 1 20 2.0 14
Oil check bolt (crankcase) M6 × 1.0 1 10 1.0 7.2
Oil strainer M6 × 1.0 1 10 1.0 7.2
Crankcase bearing stopper M6 × 1.0 4 14 1.4 10
Crankcase bearing stopper M6 × 1.0 8 10 1.0 7.2
Drive axle oil seal stopper M6 × 1.0 2 10 1.0 7.2
Ratchet wheel guide M6 × 1.0 2 12 1.2 8.7
Kickstarter crank M8 × 1.25 1 33 3.3 24
Screw (kickstarter crank) M6 × 1.0 1 7 0.7 5.1
Starter clutch M6 × 1.0 6 16 1.6 11
Primary drive gear M20 × 1.0 1 110 11.0 80
Clutch boss M20 × 1.0 1 75 7.5 54
Clutch cable adjust bolt and locknut M8 × 1.0 1 4 0.4 2.9
Clutch spring M6 × 1.0 6 10 1.0 7.2
Balancer M10 × 1.0 1 45 4.5 32
Balancer driven gear M14 × 1.0 1 50 5.0 36
Balancer weight plate M6 × 1.0 3 10 1.0 7.2
Drive sprocket M20 × 1.0 1 75 7.5 54
Drive chain sprocket cover M6 × 1.0 2 7 0.7 5.1
Shift pedal M6 × 1.0 1 12 1.2 8.7
Shift guide M6 × 1.0 2 10 1.0 7.2
Stopper lever M6 × 1.0 1 10 1.0 7.2
Segment M8 × 1.25 1 30 3.0 22Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb

2-15
TIGHTENING TORQUES
△Driven sprocket and wheel hub M8 × 1.25 6 50 5.0 36
△Nipple (spoke) — 72 3 0.3 2.2
△Disc cover and rear brake caliper M6 × 1.0 2 10 1.0 7.2
△Protector and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Chain puller adjust bolt and locknut M8 × 1.25 2 19 1.9 13
Engine mounting:
△Engine upper bracket and frame M10 × 1.25 4 55 5.5 40
△Engine lower bracket and frame M8 × 1.25 4 34 3.4 24
△Engine and engine bracket (lower) M10 × 1.25 1 53 5.3 38
△Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
△Engine and frame (lower) M10 × 1.25 1 53 5.3 38
△Engine guard M6 × 1.0 3 7 0.7 5.1
Regulator mounting M6 × 1.0 2 7 0.7 5.1
△Pivot shaft and nut M16 × 1.5 1 85 8.5 61
△Relay arm and swingarm M14 × 1.5 1 70 7.0 50
△Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
△Connecting rod and frame M14 × 1.5 1 80 8.0 58
△Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
△Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
△Rear frame and frame (upper) M8 × 1.25 1 38 3.8 27
△Rear frame and frame (lower) M8 × 1.25 2 32 3.2 23
△Swingarm and brake hose holder M5 × 0.8 4 2 0.2 1.4
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Drive chain tensioner mounting (upper) M8 × 1.25 1 16 1.6 11
Drive chain tensioner mounting (lower) M8 × 1.25 1 16 1.6 11
Chain support and swingarm M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
△Fuel tank mounting M6 × 1.0 2 9 0.9 6.5
△Fuel tank and fuel cock M6 × 1.0 2 4 0.4 2.9
Fuel tank and seat set bracket M6 × 1.0 1 7 0.7 5.1
Fuel tank and fuel tank bracket M6 × 1.0 4 7 0.7 5.1
Seat mounting M8 × 1.25 2 22 2.2 16
△Side cover mounting M6 × 1.0 2 7 0.7 5.1
△Air scoop and fuel tank M6 × 1.0 6 7 0.7 5.1
△Air scoop and radiator panel (lower) M6 × 1.0 2 6 0.6 4.3
△Front fender mounting M6 × 1.0 4 7 0.7 5.1
△Rear fender mounting (front) M6 × 1.0 2 7 0.7 5.1
△Rear fender mounting (rear) M6 × 1.0 2 11 1.1 8.0
Multi-function display bracket mounting M6 × 1.0 2 7 0.7 5.1
Multi-function display mounting M5 × 0.8 2 4 0.4 2.9
Plate 1 and protector M5 × 0.8 2 4 0.4 2.9
Plate 2 and protector — 2 0.5 0.05 0.36
Speed sensor lead holder and under bracket M6 × 1.0 1 13 1.3 9.4
Headlight body and headlight unit — 2 1 0.1 0.7Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb

2-17
TIGHTENING TORQUES
GENERAL TORQUE
SPECIFICATIONS
This chart specifies torque for stan-
dard fasteners with standard I.S.O.
pitch threads. Torque specifications
for special components or assem-
blies are included in the applicable
sections of this book. To avoid war-
page, tighten multi-fastener assem-
blies in a crisscross fashion, in
progressive stages, until full torque is
reached. Unless otherwise specified,
torque specifications call for clean,
dry threads. Components should be
at room temperature.A. Distance between flats
B. Outside thread diameter
DEFINITION OF UNITS
A
(Nut)B
(Bolt
)TORQUE SPECIFI-
CATION
Nm m•kg ft•lb
10
mm6 mm 6 0.6 4.3
12
mm8 mm 15 1.5 11
14
mm10
mm30 3.0 22
17
mm12
mm55 5.5 40
19
mm14
mm85 8.5 61
22
mm16
mm130 13 94
Unit Read Definition Measure
mm
millimeter 10-3 meter Length
cmcentimeter 10-2 meter Length
kgkilogram 103 gram Weight
NNewton 1 kg × m/sec2Force
NmNewton meter N × m Torque
m•kgMeter kilogram m × kg Torque
PaPascal N/m2Pressure
N/mmNewton per millimeter N/mm Spring rate
LLiter — Volume or capacity
cm3Cubic centimeter — Volume or capacity
r/minRevolution per minute — Engine speed

2-22
CABLE ROUTING DIAGRAM
A. Insert the end of the fuel tank
breather hose into the hole in
the steering stem.
B. Fasten the throttle cable, hot
starter cable and rectifier/regula-
tor lead onto the frame. Locate
the clamp under the throttle ca-
ble on the right side of the frame,
and face its ends, as well as the
tie ends, downward.
C. Fasten the diode (at the mark-
ing), throttle cable and hot start-
er cable onto the frame. Locate
the clamp end facing toward the
lower right of the frame and with
the tie end facing downward.
D. Fasten the wire harness, throttle
position sensor lead and clutch
cable onto the frame. Pass the
clamp through the hole in the
stay (air cut-off valve). Locate
the clamp end facing toward the
lower side of the frame and cut
off the tie end.
E. Pass the carburetor breather
hoses, carburetor overflow hose
and catch tank breather hose
between the connecting rod and
cross tube (frame).
F. Pass the neutral switch lead on
the inside of the engine bracket.
G. Fasten the neutral switch lead
and AC magneto lead onto the
frame. Locate the clamp end
facing toward the outside of the
frame and tie end facing toward
the rear of the frame.
H. Fasten the AC magneto lead
and neutral switch lead onto the
frame. Locate the clamp end
facing toward the rear of the
frame and cut off the tie end.
I. Pass the neutral switch lead and
AC magneto lead on the inside
of the wire harness.
J. Fasten the AC magneto lead
and neutral switch lead onto the
frame.
K. Pass the wire harness through
the cable guide.
L. Locate the couplers in the frame
recess.
M. Pass the carburetor breather
hoses, carburetor overflow hose
and catch tank breather hose so
that the hoses do not contact the
rear shock absorber.
N. Secure the coupler by pushing it
into the hole in the headlight
unit.
O. Fasten the throttle position sen-
sor lead and the hot starter ca-
ble.P. Locate the clamp between the
hot starter cable protector and
rubber cap.

2-26
CABLE ROUTING DIAGRAM
A. Fasten the wire harness to the
upper engine bracket (left side).
Locate the clamp end facing to-
ward the upper side of the frame
with the tie end cut off on the in-
side of the frame.
B. Fasten the wire harness to the
upper engine bracket (left side).
Locate the clamp end facing to-
ward the upper side of the frame
with the tie end cut off on the in-
side of the frame. Clamp the
wire harness at the marking.
C. Pass the starter motor lead
through the hole in the relay
holder.
D. Fit the cover securely.
E. Connect the wire harness to the
starter relay.
F. Fasten the catch tank breather
hose and catch tank hose to the
rear frame. Clamp them close to
where they are joined to the
frame. Fasten the pipe tightly
enough not to crush it. Locate
the clamp end facing toward the
rear of the frame with the tie end
facing downward.
G. Fasten the (three) CDI unit leads
and taillight lead to the rear
frame. Locate the clamp end
facing toward the upper side of
the frame and cut off the tie end.
H. Connect the negative battery
lead to the battery negative ter-
minal.
I. Connect the negative battery
lead to the wire harness.
J. Fasten the wire harness to the
rear frame. Locate the clamp
end facing toward the upper side
of the frame and the tie end to-
ward the inside of the frame.
Clamp the wire harness at the
marking.
K. Pass the wire harness, starter
relay lead, starting circuit cut-off
relay lead and negative battery
lead through the hole in the relay
holder.
L. Fasten the (three) CDI unit leads
and taillight lead to the rear
frame. Locate the clamp end
facing toward the lower side of
the frame and cut off the tie end.
M. Fasten the taillight lead to the
rear frame. Locate the clamp
end facing toward the upper side
of the frame and cut off the tie
end.
N. Do not allow the taillight lead to
slacken.O. Locate the CDI unit lead be-
tween the CDI unit and rear
fender.
P. Locate the CDI unit coupler in
the clearance between the up-
per side of the CDI unit and low-
er side of the catch tank stay.
Q. Locate the CDI unit lead be-
tween the CDI unit and rear
frame.

2-27
CABLE ROUTING DIAGRAM
1. Throttle cable
2. Clamp
3. Brake hose
4. Clutch cable
5. Hose guide
6. Main switch coupler
7. Wire harness
8. Headlight coupler
9. Hot starter cable
10. Multi-function display bracket
11. Main switch12. Upper bracket
13. Clutch switch coupler
14. Engine stop switch coupler
15. Multi-function display coupler
16. Start switch coupler
17. Speed sensor coupler
18. Speed sensor lead

2-28
CABLE ROUTING DIAGRAM
A. Fasten the start switch lead to
the handlebar with the plastic
bands.
B. Fasten the engine stop switch
lead and clutch switch lead to
the handlebar with the plastic
bands.
C. Pass the brake hose through
the hose guides.
D. Secure the coupler by inserting
it into the multi-function display
bracket.
E. Pass the throttle cables, clutch
cable and hot starter cable be-
tween the upper bracket and
multi-function display bracket.
F. Fasten the multi-function display
leads to the bracket. Cut off the
tie end.
G. Secure the coupler by pushing it
into the hole in the multi-function
display bracket.
H. Secure the wire harness clip by
pushing it into the hole in the
multi-function display bracket on
the inside.
I. Fasten the main switch lead
(wire harness side) to the multi-
function display bracket. Locate
the clamp end facing toward the
lower side of the frame and cut
off the tie end.
J. Pass the speed sensor lead
through the guide on the outside
of the front fork.