engine YAMAHA YZ450F 2014 Owner's Manual

ENGINE SPECIFICATIONS
2-2
EAS1SL1053
ENGINE SPECIFICATIONS
Engine
Engine type Liquid cooled 4-stroke, DOHC
Displacement 449 cm3
Cylinder arrangement Single cylinder
Bore  stroke 97.0  60.8 mm (3.82  2.39 in)
Compression ratio 12.50:1
Starting system Kickstarter
Fuel
Recommended fuel Premium unleaded gasoline only
Fuel tank capacity 7.5 L (1.98 US gal, 1.65 Imp.gal)
Engine oil
Lubrication system Wet sump
Recommended brand YAMALUBE
Type SAE 10W-30, SAE 10W-40, SAE 15W-40, 
SAE 20W-40 or SAE 20W-50
Recommended oil grade API service SG type or higher, 
JASO standard MA
Engine oil quantity
Quantity (disassembled) 0.95 L (1.00 US qt, 0.84 Imp.qt)
With oil filter element replacement 0.69 L (0.73 US qt, 0.61 Imp.qt)
Without oil filter element replacement 0.67 L (0.71 US qt, 0.59 Imp.qt)
Oil filter
Oil filter type Paper
Oil pump
Oil pump type Trochoid
Inner-rotor-to-outer-rotor-tip clearance Less than 0.150 mm (0.0059 in)
Limit 0.20 mm (0.0079 in)
Outer-rotor-to-oil-pump-housing clearance 0.13–0.18 mm (0.0051–0.0071 in)
Limit 0.24 mm (0.0094 in)
Oil-pump-housing-to-inner-and-outer-rotor 
clearance 0.06–0.11 mm (0.0024–0.0043 in)
Limit 0.17 mm (0.0067 in)
Cooling system
Radiator capacity (including all routes) 1.04 L (1.10 US qt, 0.92 Imp.qt)
Radiator capacity 0.57 L (0.60 US qt, 0.50 mp.qt)
Radiator cap opening pressure 108–137 kPa (1.08–1.37 kg/cm2 15.7–19.9 psi)
Radiator core
Width 112.6 mm (4.43 in)
Height 235.0 mm (9.25 in)
Depth 28.0 mm (1.10 in)
Water pump
Water pump type Single suction centrifugal pump
Spark plug
Manufacturer/model NGK/CR8E
Spark plug gap 0.7–0.8 mm (0.028–0.031 in)

ENGINE SPECIFICATIONS
2-3
Cylinder head
Volume 25.98–26.78 cm3 (1.59–1.63 cu.in)
Warpage limit 0.05 mm (0.0020 in)
Camshaft
Drive system Chain drive (left)
Camshaft cap inside diameter 22.000–22.021 mm (0.8661–0.8670 in)
Camshaft journal diameter 21.959–21.972 mm (0.8645–0.8650 in)
Camshaft-journal-to-camshaft-cap clearance 0.028–0.062 mm (0.0011–0.0024 in)
Camshaft lobe dimensions
Intake A 37.730–37.830 mm (1.4854–1.4894 in)
Limit 37.630 mm (1.4815 in)
Intake B 27.950–28.050 mm (1.1004–1.1043 in)
Limit 27.850 mm (1.0965 in)
Exhaust A 33.540–33.640 mm (1.3205–1.3244 in)
Limit 33.440 mm (1.3165 in)
Exhaust B 24.769–24.869 mm (0.9752–0.9791 in)
Limit 24.669 mm (0.9712 in)
Camshaft runout limit 0.015 mm (0.0006 in)
Timing chain
Tensioning system Automatic
Valve, valve seat, valve guide
Valve clearance (cold)
Intake 0.13–0.20 mm (0.0051–0.0079 in)
Exhaust 0.20–0.25 mm (0.0079–0.0098 in)
Valve dimensions
Valve head diameter A (intake) 36.90–37.10 mm (1.4528–1.4606 in)
Valve head diameter A (exhaust) 30.40–30.60 mm (1.1968–1.2047 in)
Valve face width B (intake) 1.697 mm (0.0668 in)
Valve face width B (exhaust) 1.768 mm (0.0696 in)
A
B
A
B

ENGINE SPECIFICATIONS
2-4
Valve seat width C (intake) 0.90–1.10 mm (0.0354–0.0433 in)
Valve seat width C (exhaust) 0.90–1.10 mm (0.0354–0.0433 in)
Valve margin thickness D (intake) 1.20 mm (0.0472 in)
Valve margin thickness D (exhaust) 0.85 mm (0.0335 in)
Valve stem diameter (intake) 5.475–5.490 mm (0.2156–0.2161 in)
Limit 5.445 mm (0.2144 in)
Valve stem diameter (exhaust) 5.465–5.480 mm (0.2152–0.2157 in)
Limit 5.435 mm (0.2140 in)
Valve guide inside diameter (intake) 5.500–5.512 mm (0.2165–0.2170 in)
Limit 5.550 mm (0.2185 in)
Valve guide inside diameter (exhaust) 5.500–5.512 mm (0.2165–0.2170 in)
Limit 5.550 mm (0.2185 in)
Valve-stem-to-valve-guide clearance (intake) 0.010–0.037 mm (0.0004–0.0015 in)
Limit 0.080 mm (0.0032 in)
Valve-stem-to-valve-guide clearance (exhaust) 0.020–0.047 mm (0.0008–0.0019 in)
Limit 0.100 mm (0.0039 in)
Valve stem runout 0.010 mm (0.0004 in)
Valve spring
Free length (intake) 40.76 mm (1.60 in)
Limit 39.76 mm (1.57 in)
Free length (exhaust) 37.01 mm (1.46 in)
Limit 36.01 mm (1.42 in)
Installed length (intake) 34.78 mm (1.37 in)
Installed length (exhaust) 30.83 mm (1.21 in)
Spring rate K1 (intake) 31.90 N/mm (3.25 kgf/mm, 182.15 lbf/in)
Spring rate K2 (intake) 41.37 N/mm (4.22 kgf/mm, 236.22 lbf/in)
Spring rate K1 (exhaust) 21.46 N/mm (2.19 kgf/mm, 122.54 lbf/in)
Spring rate K2 (exhaust) 27.84 N/mm (2.84 kgf/mm, 158.97 lbf/in)
Installed compression spring force (intake) 178.00–204.00 N (18.15–20.80 kgf, 
40.01–45.86 lbf)
Installed compression spring force (exhaust) 124.00–142.00 N (12.64–14.48 kgf, 
27.88–31.92 lbf)
Spring tilt (intake) 2.5 °/1.8 mm (2.5 °/0.07 in)
Spring tilt (exhaust) 2.5 °/1.6 mm (2.5 °/0.06 in)
C
D

ENGINE SPECIFICATIONS
2-5
Winding direction (intake) Clockwise
Winding direction (exhaust) Clockwise
Cylinder
Bore 97.000–97.010 mm (3.8189–3.8193 in)
Taper limit 0.050 mm (0.0020 in)
Out of round limit 0.050 mm (0.0020 in)
Piston
Piston-to-cylinder clearance 0.030–0.055 mm (0.0012–0.0022 in)
Limit 0.15 mm (0.006 in)
Diameter D 96.955–96.970 mm (3.8171–3.8177 in)
Height H 9.0 mm (0.35 in)
Offset 0.00 mm (0.0000 in)
Piston pin bore inside diameter 18.004–18.015 mm (0.7088–0.7093 in)
Limit 18.045 mm (0.7104 in)
Piston pin outside diameter 17.991–18.000 mm (0.7083–0.7087 in)
Limit 17.971 mm (0.7075 in)
Piston ring
Top ring
Ring type Barrel
Dimensions (B  T) 1.00  3.30 mm (0.04  0.13 in)
End gap (installed) 0.20–0.30 mm (0.0079–0.0118 in)
Limit 0.55 mm (0.0217 in)
Ring side clearance 0.015–0.065 mm (0.0006–0.0026 in)
Limit 0.120 mm (0.0047 in)
2nd ring
Ring type Taper
Dimensions (B  T) 1.00  3.10 mm (0.04  0.12 in)
End gap (installed) 0.35–0.50 mm (0.0138–0.0197 in)
Limit 0.85 mm (0.0335 in)
Ring side clearance 0.020–0.060 mm (0.0008–0.0024 in)
Limit 0.120 mm (0.0047 in)
H
D
T
B
B
T

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