2014 YAMAHA YZ450F engine

ENGINE SPECIFICATIONS
2-6
Oil ring
Dimensions (B  T) 1.50  2.55 mm (0.06  0.10 in)
End gap (installed) 0.20–0.50 mm (0.0079–0.0197 in)
Crankshaft
Width A 61.95–62.00 mm (2.439–2.441 in)
Runout limit C 0.030 mm (0.0012 in)
Big end side clearance D 0.150–0.450 mm (0.0059–0.0177 in)
Balancer
Balancer drive method Gear
Clutch
Clutch type Wet, multiple-disc
Clutch release method Inner push, cam push
Clutch lever free play 7.0–12.0 mm (0.28–0.47 in)
Friction plate thickness 2.92–3.08 mm (0.115–0.121 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 8 pcs
Clutch plate thickness 1.10–1.30 mm (0.043–0.051 in)
Plate quantity 7 pcs
Warpage limit 0.10 mm (0.0039 in)
Clutch spring free length 48.00 mm (1.89 in)
Minimum length 47.00 mm (1.85 in)
Spring quantity 6 pcs
Push rod bending limit 0.10 mm (0.0039 in)
Transmission
Transmission type Constant mesh 5-speed
Primary reduction system Spur gear
Primary reduction ratio 2.609 (60/23)
Final drive Chain
Secondary reduction ratio 3.769 (49/13)
Operation Left foot operation
Gear ratio
1st 1.929 (27/14)
2nd 1.533 (23/15)
3rd 1.300 (26/20)
4th 1.091 (24/22)
5th 0.952 (20/21)
B
T
CC
D
A

ENGINE SPECIFICATIONS
2-7
Shifting mechanism
Shift mechanism type Shift drum and guide bar
Shift fork guide bar bending limit 0.050 mm (0.0020 in)
Shift fork thickness 4.85 mm (0.1909 in)
Decompression device
Device type Auto decomp
Air filter
Air filter element Wet element
Air filter oil grade Foam air-filter oil
Fuel pump
Pump type Electrical
Fuel injector
Model/quantity 1010/1
Resistance 12 
Throttle body
Type/quantity 30RA-A13M/1
ID mark 1SL1 00
Fuel pressure 324.0 kPa (3.24 kgf/cm2, 47.0 psi)
Throttle position sensor
Resistance 6.30 k
Output voltage (at idle) 0.48–0.52 V
Fuel injection sensor
Crankshaft position sensor resistance 248–372 
Intake air pressure sensor output voltage 3.57–3.71 V at 101.3 kPa
Intake air temperature sensor resistance 290–390  at 80 °C (176 °F)
Coolant temperature sensor resistance 2.51–2.78 k at 20°C (68°F)
210–221  at 100°C (212°F)
Idling condition
Engine idling speed 1900–2100 r/min
CO% 6.8–9.2 %
Intake vacuum 30.5–37.8 kPa (229–284 mmHg, 
9.0–11.2 inHg)
Water temperature 70–80 °C (158–176 °F)
Oil temperature 55-65 °C (131–149 °F)
Throttle grip free play 3.0–5.0 mm (0.12–0.20 in)

ELECTRICAL SPECIFICATIONS
2-12
EAS1SL1055
ELECTRICAL SPECIFICATIONS
Voltage
System voltage 12 V
Ignition system
Ignition system TCI
Advancer type Digital
Ignition timing (B.T.D.C.) 10.0 ° at 2000 r/min
Engine control unit
Model/manufacturer 1SL0/YAMAHA (USA) (CAN)
1SL1/YAMAHA (EUR) (JPN) (AUS) (NZL)
(ZAF)
Ignition coil
Minimum ignition spark gap 6.0 mm (0.24 in)
Primary coil resistance 2.16–2.64 
Secondary coil resistance 8.64–12.96 k
AC magneto
Standard output 14.0 V, 95 W at 5000 r/min
Stator coil resistance 0.624–0.936 
Rectifier/regulator
Regulator type Semi conductor-short circuit
No load regulated voltage 14.1–14.9 V
Rectifier capacity (DC) 23.0 A

TIGHTENING TORQUES
2-14
EAS1SL1057ENGINE TIGHTENING TORQUES
TIP
- marked portion shall be checked for torque tightening after break-in or before each race.
ITEMThread
sizeQ’tyTIGHTENING TORQUESRemarks
Camshaft cap boltM6810 Nm (1.0 m·kgf, 7.2 ft·lbf)
Cylinder head blind plugM12128 Nm (2.8 m·kgf, 20 ft·lbf)
Spark plugM10113 Nm (1.3 m·kgf, 9.4 ft·lbf)
Cylinder head stud bolt (exhaust
pipe)M637 Nm (0.7 m·kgf, 5.1 ft·lbf)
Cylinder head boltsM94See TIP.*1
Cylinder head boltsM6210 Nm (1.0 m·kgf, 7.2 ft·lbf)
Cylinder head cover boltM6310 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil passage plug (cylinder head)M8115 Nm (1.5 m·kgf, 11 ft·lbf)
Cylinder boltM6110 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil pressure check boltM6210 Nm (1.0 m·kgf, 7.2 ft·lbf)
Balancer weight plate screwM6310 Nm (1.0 m·kgf, 7.2 ft·lbf)
Balancer driven gear nutM14150 Nm (5.0 m·kgf, 36 ft·lbf)
Use a
lock
washer.
Balancer nutM10145 Nm (4.5 m·kgf, 33 ft·lbf)
Use a
lock
washer.
Timing chain guide stopper plate
(exhaust side)M6110 Nm (1.0 m·kgf, 7.2 ft·lbf)
Timing chain tensioner cap boltM616 Nm (0.6 m·kgf, 4.3 ft·lbf)
Timing chain tensioner boltM6210 Nm (1.0 m·kgf, 7.2 ft·lbf)
Coolant drain boltM6110 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator hose clamp screwM681.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Radiator boltM6410 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator pipe bolt M6110 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator pipe joint bolt M6110 Nm (1.0 m·kgf, 7.2 ft·lbf)
Water pump housing cover boltM6410 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil pump boltM525 Nm (0.5 m·kgf, 3.6 ft·lbf)
Oil pump cover screwM412.0 Nm (0.20 m·kgf, 1.4 ft·lbf)
Oil strainer boltM6110 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil passage cover bolt (left crank-
case)M6110 Nm (1.0 m·kgf, 7.2 ft·lbf)
Throttle cable cover boltM513.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Throttle body joint boltM6210 Nm (1.0 m·kgf, 7.2 ft·lbf)
Throttle body joint clamp boltM513.0 Nm (0.30 m·kgf, 2.2 ft·lbf)
Air filter joint clamp boltM413.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Air filter case boltM637 Nm (0.7 m·kgf, 5.1 ft·lbf)
LT
M
LT
LT
LT

TIGHTENING TORQUES
2-15
Air filter boltM6 1 2.0 Nm (0.20 m·kgf, 1.4 ft·lbf)
Air filter case cover bolt M6 3 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Air filter guide holder screw M5 8 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Air filter case cap screw M5 1 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Starter knob/Idle screw M12 1 2.1 Nm (0.21 m·kgf, 1.5 ft·lbf)
Throttle cable nut (pull) M10 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Throttle cable nut (return) M10 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Clutch cable adjuster and locknut M6 1 4.3 Nm (0.43 m·kgf, 3.1 ft·lbf)
Clutch cable locknut (engine side) M8 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Exhaust pipe nut M6 3See TIP.
*2
Exhaust pipe protector screw M6 4 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Exhaust pipe bracket bolt M8 1 20 Nm (2.0 m·kgf, 14 ft·lbf)
Frame and silencer bolt (front) M8 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Frame and silencer bolt (rear) M 8 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Exhaust pipe clamp bolt M8 2 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Silencer body bolt M5 6 8 Nm (0.8 m·kgf, 5.8 ft·lbf)
Oil nozzle bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Engine oil drain bolt M10 1 20 Nm (2.0 m·kgf, 14 ft·lbf)
Crankcase bolt M6 12 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Clutch cable holder bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Crankshaft end accessing screw M36 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Timing mark accessing screw M14 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Drive chain sprocket cover bolt M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Crankcase bearing cover plate
screw M6 8 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Crankcase bearing cover plate
screw (crankshaft) M8 4 18 Nm (1.8 m·kgf, 13 ft·lbf) Crimp.
Clutch cover bolt M6 7 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil level check window bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Left crankcase cover bolt M6 7 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Right crankcase cover bolt M6 11 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil filter element cover bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil level check window bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Kick shaft ratchet wheel guide bolt M6 2 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Kick starter lever bolt M8 1 33 Nm (3.3 m·kgf, 24 ft·lbf)
Kick starter lever boss screw M6 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Primary drive gear nut M20 1 100 Nm (10 m·kgf, 72 ft·lbf)
Clutch spring bolt M6 6 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Clutch boss nut M20 1 75 Nm (7.5 m·kgf, 54 ft·lbf)
ITEM
Thread
size Q’ty TIGHTENING TORQUES RemarksLT
LT
LT
LT
LT
LT
LT

TIGHTENING TORQUES
2-18
CHASSIS TIGHTENING TORQUES
TIP
- marked portion shall be checked for torque tightening after break-in or before each race.
ITEMThread
sizeQ’tyTIGHTENING TORQUESRemarks
Outer tube and upper bracket boltM8421 Nm (2.1 m·kgf, 15 ft·lbf)
Outer tube and lower bracket boltM8421 Nm (2.1 m·kgf, 15 ft·lbf)
Upper bracket and steering stem nutM241145 Nm (14.5 m·kgf, 105 ft·lbf)
Upper handlebar holder boltM8428 Nm (2.8 m·kgf, 20 ft·lbf)
Lower handlebar holder nutM10240 Nm (4.0 m·kgf, 29 ft·lbf)
Engine stop switch screwM310.5 Nm (0.05 m·kgf, 0.36 ft·lbf)
Lower ring nutM281See TIP.
Outer tube and damper assemblyM51230 Nm (3.0 m·kgf, 22 ft·lbf)
Inner tube and adjusterM22255 Nm (5.5 m·kgf, 40 ft·lbf)
Damper assembly and base valveM42228 Nm (2.8 m·kgf, 20 ft·lbf)
Damper assembly adjusterM12229 Nm (2.9 m·kgf, 21 ft·lbf)
Bleed screw (front fork) and base
valveM521.3 Nm (0.13 m·kgf, 0.94 ft·lbf)
Front fork protector boltM665 Nm (0.5 m·kgf, 3.6 ft·lbf)
Front fork protector and brake hose
holder boltM629 Nm (0.9 m·kgf, 6.5 ft·lbf)
Throttle grip cap screwM523.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
Clutch lever holder boltM625 Nm (0.5 m·kgf, 3.6 ft·lbf)
Clutch lever nutM614.0 Nm (0.40 m·kgf, 2.9 ft·lbf)
Clutch lever position locknutM514.8 Nm (0.48 m·kgf, 3.5 ft·lbf)
Front brake master cylinder holder
boltM629 Nm (0.9 m·kgf, 6.5 ft·lbf)
Front brake master cylinder reser-
voir cap screwM421.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Front brake lever pivot boltM616 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front brake lever pivot nutM616 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front brake lever position locknutM615 Nm (0.5 m·kgf, 3.6 ft·lbf)
Front brake hose holder and lower
bracket boltM619 Nm (0.9 m·kgf, 6.5 ft·lbf)
Front brake hose union boltM10230 Nm (3.0 m·kgf, 22 ft·lbf)
Front brake caliper boltM8228 Nm (2.8 m·kgf, 20 ft·lbf)
Front brake pad pinM10117 Nm (1.7 m·kgf, 12 ft·lbf)
Front brake pad pin plugM1012.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Front brake caliper bleed screwM816 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front wheel axle nutM181115 Nm (11.5 m·kgf, 83 ft·lbf)
Front wheel axle pinch boltM8421 Nm (2.1 m·kgf, 15 ft·lbf)
Front brake disc boltM6612 Nm (1.2 m·kgf, 8.7 ft·lbf)
LT
LT

TIGHTENING TORQUES
2-19
Rear brake disc boltM6 6 14 Nm (1.4 m·kgf, 10 ft·lbf)
Footrest bracket bolt M10 4 55 Nm (5.5 m·kgf, 40 ft·lbf)
Rear brake pedal bolt M8 1 26 Nm (2.6 m·kgf, 19 ft·lbf)
Rear brake pedal position locknut M6 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Rear brake master cylinder bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Rear brake master cylinder reservoir
cap bolt M4 2 1.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Rear brake hose union bolt M10 2 30 Nm (3.0 m·kgf, 22 ft·lbf)
Rear brake caliper bleed screw M8 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Rear brake pad pin M10 1 17 Nm (1.7 m·kgf, 12 ft·lbf)
Rear brake pad pin plug M10 1 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Rear wheel axle nut M22 1 135 Nm (13.5 m·kgf, 98 ft·lbf)
Drive chain puller adjust bolt and
locknut M8 2 21 Nm (2.1 m·kgf, 15 ft·lbf)
Rear wheel sprocket nut M8 6 42 Nm (4.2 m·kgf, 30 ft·lbf)
Nipple (spoke) — 72 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Rear brake disc cover bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Rear brake caliper protector bolt M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Engine mounting bolt (upper side) M10 2 45 Nm (4.5 m·kgf, 33 ft·lbf)
Engine mounting bolt (front side) M 10 1 59 Nm (5.9 m·kgf, 43 ft·lbf)
Engine mounting bolt (lower side) M 10 1 53 Nm (5.3 m·kgf, 38 ft·lbf)
Engine bracket bolt (upper side) M8 4 34 Nm (3.4 m·kgf, 25 ft·lbf)
Engine bracket bolt (front side) M8 4 34 Nm (3.4 m·kgf, 25 ft·lbf)
Rear frame and frame bolt M8 4 32 Nm (3.2 m·kgf, 23 ft·lbf)
Engine guard bolt (right side) M6 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Pivot shaft and nut M16 1 85 Nm (8.5 m·kgf, 61 ft·lbf)
Rear shock absorber assembly up-
per bolt M10 1 56 Nm (5.6 m·kgf, 41 ft·lbf)
Rear shock absorber assembly low-
er bolt M10 1 53 Nm (5.3 m·kgf, 38 ft·lbf)
Rear shock absorber locknut M60 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Relay arm bolt (swingarm side) M14 1 70 Nm (7.0 m·kgf, 51 ft·lbf)
Connecting arm bolt (relay arm side) M14 1 80 Nm (8.0 m·kgf, 58 ft·lbf)
Connecting arm bolt (frame side) M14 1 80 Nm (8.0 m·kgf, 58 ft·lbf)
Swingarm and brake hose holder
screw M5 4 3.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Drive chain tensioner bolt (upper
side) M8 1 16 Nm (1.6 m·kgf, 12 ft·lbf)
Drive chain tensioner bolt (lower
side) M8 1 16 Nm (1.6 m·kgf, 12 ft·lbf)
Drive chain support bolt M6 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
ITEM
Thread
size Q’ty TIGHTENING TORQUES RemarksLT
LT

LUBRICATION POINTS AND LUBRICANT TYPES
2-21
EAS1SL1059
LUBRICATION POINTS AND LUBRICANT TYPES
EAS1SL1060ENGINE
Lubrication pointLubricant types
Oil seal lips
Bearing
O-ring
Cylinder head bolt threads, seats, washers
Valve stems
Valve stem ends
Valve lifter outer surface
Camshaft lobe and journal
Valve lifter top surface
Crankshaft journal
Crankshaft big end thrust surfaces
Piston outer surface
Piston pin outer surface
Decompression system moving parts
Water pump impeller shaft
Oil pump rotors (inner and outer)
Oil passage gasket
Oil pump shaft
Kick gear and ratchet wheel
Kick shaft
Kick idle gear inner surface
Ratchet wheel and ratchet wheel guide contacting portion
Primary drive gear nut threads and contacting surface
Clutch boss nut threads and contacting surface
Primary driven gear inner surface and end surface
Clutch push rod washer
Clutch push rod 1 outer surface
Clutch push rod 1 thrust surface
Clutch push rod 2 outer surface
Push lever shaft outer surface
Transmission gear inner surface (wheel and pinion) and collar
Transmission gears (shift fork groove)
Shift cam grooves
Shift fork and shift fork guide outer surface
Shift shaft
Shift lever assembly moving parts
LS
E
LS
M
M
M
E
M
E
M
E
E
E
E
E
E
LS
E
M
E
E
M
E
E
E
E
E
E
E
E
M
E
E
E
E
E