2009 YAMAHA YZ450F Owners Manual

2-3
MAINTENANCE SPECIFICATIONS
MAINTENANCE SPECIFICATIONS
ENGINEWheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 314 mm (12.4 in)
Electrical:
Ignition system CDI magneto
Item Standard Limit
Cylinder head:
Warp limit ---- 0.05 mm (0.002
in)
Cylinder:
Bore size 95.00–95.01 mm (3.7402–3.7406 in) ----
Out of round limit ---- 0.05 mm (0.002
in)
Camshaft:
Drive method Chain drive (Left) ----
Camshaft cap inside diameter 22.000–22.021 mm (0.8661–0.8670 in) ----
Camshaft outside diameter 21.959–21.972 mm (0.8645–0.8650 in) ----
Shaft-to-cap clearance 0.028–0.062 mm (0.0011–0.0024 in) 0.08 mm (0.003
in)
Cam dimensions
Intake "A" 31.200–31.300 mm (1.2283–1.2323 in) 31.100 mm
(1.2244 in)
Intake "B" 22.550–22.650 mm (0.8878–0.8917 in) 22.450 mm
(0.8839 in)
Exhaust "A" 30.900–31.000 mm (1.2165–1.2205 in) 30.800 mm
(1.2126 in)
Exhaust "B" 22.468–22.568 mm (0.8846–0.8885 in) 22.368 mm
(0.8806 in)
Camshaft runout limit ---- 0.03 mm
(0.0012 in)

2-4
MAINTENANCE SPECIFICATIONS
Timing chain:
Timing chain type/No. of links 98XRH2010-118M/118 ----
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) 26.9–27.1 mm (1.0591–1.0669 in) ----
"A" head diameter (EX) 27.9–28.1 mm (1.0984–1.1063 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 mm (0.0394 in) 0.85 mm (0.033
in)
"D" margin thickness (EX) 1 mm (0.0394 in) 0.85 mm (0.033
in)
Stem outside diameter (IN) 4.475–4.490 mm (0.1762–0.1768 in) 4.445 mm
(0.1750 in)
Stem outside diameter (EX) 4.965–4.980 mm (0.1955–0.1961 in) 4.935 mm
(0.1943 in)
Guide inside diameter (IN) 4.500–4.512 mm (0.1772–0.1776 in) 4.550 mm
(0.1791 in)
Guide inside diameter (EX) 5.000–5.012 mm (0.1969–0.1973 in) 5.050 mm
(0.1988 in) Item Standard Limit

2-5
MAINTENANCE SPECIFICATIONS
Stem-to-guide clearance (IN) 0.010–0.037 mm (0.0004–0.0015 in) 0.08 mm (0.003
in)
Stem-to-guide clearance (EX) 0.020–0.047 mm (0.0008–0.0019 in) 0.10 mm (0.004
in)
Stem runout limit ---- 0.01 mm
(0.0004 in)
Valve seat width (IN) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)
Valve seat width (EX) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)
Valve spring:
Free length (IN) 37.03 mm (1.46 in) 36.03 mm (1.42
in)
Free length (EX) 37.68 mm (1.48 in) 36.68 mm (1.44
in)
Set length (valve closed) (IN) 27.87 mm (1.10 in) ----
Set length (valve closed) (EX) 27.38 mm (1.08 in) ----
Compressed force (installed) (IN) 111.3–127.9 N at 27.87 mm (11.3–13.0 kg
at 27.87 mm, 24.91–28.66 lb at 1.10 in)----
Compressed force (installed) (EX) 127.4–146.4 N at 27.38 mm (13.0–14.9 kg
at 27.38 mm, 28.66–32.85 lb at 1.08 in)----
Tilt limit* (IN) ---- 2.5°/1.61 mm
(2.5°/0.063 in)
Tilt limit* (EX) ---- 2.5°/1.65 mm
(2.5°/0.065 in)
Direction of winding (top view) (IN) Clockwise ----
Direction of winding (top view) (EX) Clockwise ----
Piston:
Piston to cylinder clearance 0.020–0.045 mm (0.0008–0.0018 in) 0.1 mm (0.004
in)
Piston size "D" 94.965–94.980 mm (3.7388–3.7394 in) ----
Measuring point "H" 8 mm (0.315 in) ----Item Standard Limit

2-6
MAINTENANCE SPECIFICATIONS
Piston off-set 1 mm (0.0394 in) ----
Piston pin bore inside diameter 18.004–18.015 mm (0.7088–0.7093 in) 18.045 mm
(0.7104 in)
Piston pin outside diameter 17.991–18.000 mm (0.7083–0.7087 in) 17.971 mm
(0.7075 in)
Piston rings:
Top ring:
Type Barrel ----
Dimensions (B × T) 1.2 × 3.5 mm (0.05 × 0.14 in) ----
End gap (installed) 0.20–0.30 mm (0.008–0.012 in) 0.55 mm (0.022
in)
Side clearance (installed) 0.030–0.065 mm (0.0012–0.0026 in) 0.12 mm (0.005
in)
2nd ring:
Type Taper ----
Dimensions (B × T) 1.00 × 3.35 mm (0.04 × 0.13 in) ----
End gap (installed) 0.35–0.50 mm (0.014–0.020 in) 0.85 mm (0.033
in)
Side clearance 0.020–0.055 mm (0.0008–0.0022 in) 0.12 mm (0.005
in)
Oil ring:
Dimensions (B × T) 2.0 × 2.9 mm (0.08 × 0.11 in) ----
End gap (installed) 0.2–0.5 mm (0.01–0.02 in) ----
Crankshaft:
Crank width "A" 61.95–62.00 mm (2.439–2.441 in) ----
Runout limit "C" 0.03 mm (0.0012 in) 0.05 mm (0.002
in)
Big end side clearance "D" 0.15–0.45 mm (0.0059–0.0177 in) 0.50 mm (0.02
in)
Small end free play "F" 0.4–1.0 mm (0.02–0.04 in) 2.0 mm (0.08
in)
Balancer:
Balancer drive method Gear ----Item Standard Limit

2-7
MAINTENANCE SPECIFICATIONS
Air filter oil grade: Foam-air-filter oil or equivalent oil ----
Clutch:
Friction plate thickness 2.92–3.08 mm (0.115–0.121 in) 2.8 mm (0.110
in)
Quantity 8 ----
Clutch plate thickness 1.5–1.7 mm (0.059–0.067 in) ----
Quantity 7 ----
Warp limit ---- 0.1 mm (0.004
in)
Clutch spring free length 50.0 mm (1.97 in) 49.0 mm (1.93
in)
Quantity 6 ----
Clutch housing thrust clearance 0.10–0.35 mm (0.0039–0.0138 in) ----
Clutch housing radial clearance 0.010–0.044 mm (0.0004–0.0017 in) ----
Clutch release method Inner push, cam push ----
Shifter:
Shifter type Cam drum and guide bar ----
Guide bar bending limit ---- 0.05 mm (0.002
in)
Kickstarter:
Type Kick and ratchet type ----
Carburetor:
Type/manufacturer FCR-MX39/KEIHIN ----
I. D. mark 2S2B B0 ----
Main jet (M.J) #160 ----
Main air jet (M.A.J) ø2.0 ----
Jet needle - clip position (J.N) NFLR-3 ----
Cutaway (C.A) 1.5 ----
Pilot jet (P.J) #45 ----
Pilot air jet (P.A.J) #100 ----
Pilot outlet (P.O) ø0.9 ----
Pilot screw (example) (P.S) 1-1/2 ----
Bypass (B.P) ø1.0 ----
Valve seat size (V.S) ø3.8 ----
Starter jet (G.S) #72 ----
Leak jet (Acc.P) #55 ----
Float height (F.H) 8 mm (0.31 in) ----
Engine idle speed 1,900–2,100 r/min ----
Intake vacuum 28.0–33.3 kPa (210–250 mmHg, 8.27–
9.84 inHg)----
Hot starter lever free play 3–6 mm (0.12–0.24 in) ----Item Standard Limit

2-8
MAINTENANCE SPECIFICATIONS
CHASSISLubrication system:
Oil filter type Paper type ----
Oil pump type Trochoid type ----
Tip clearance 0.12 mm or less (0.0047 in or less) 0.20 mm (0.008
in)
Side clearance 0.09–0.17 mm (0.0035–0.0067 in) 0.24 mm (0.009
in)
Housing and rotor clearance 0.03–0.10 mm (0.0012–0.0039 in) 0.17 mm (0.007
in)
Bypass valve setting pressure 40–80 kPa (0.4–0.8 kg/cm
2, 5.69–11.38
psi)----
Cooling:
Radiator core size
Width 120.2 mm (4.73 in) ----
Height 240 mm (9.45 in) ----
Thickness 22 mm (0.87 in) ----
Radiator cap opening pressure 110 kPa (1.1 kg/cm
2, 15.6 psi) ----
Radiator capacity (total) 0.56 L (0.49 Imp qt, 0.59 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension: USA, CDN EUROPE, AUS, NZ, ZA
Front fork travel 300 mm (11.8 in)←----
Fork spring free length 454 mm (17.9 in)←449 mm (17.7
in)
Spring rate, STD K = 4.6 N/mm (0.469 kg/
mm, 26.3 lb/in)←----
Optional spring Yes←----
Oil capacity 541 cm
3 (19.0 lmp oz,
18.3 US oz)531 cm3 (18.7 lmp oz,
18.0 US oz)----
Oil grade Suspension oil "S1"←----
Inner tube outer diameter 48 mm (1.89 in)←----
Front fork top end 5 mm (0.20 in)←----
Rear suspension: USA, CDN EUROPE, AUS, NZ, ZA
Shock absorber travel 131.5 mm (5.18 in)←----
Spring free length Approx.275 mm (10.83
in)←----
Fitting length*
I.D. mark (Pink/1) 266 mm (10.47 in) 263 mm (10.35 in) ----
I.D. mark (Pink/2) 272 mm (10.71 in) 269 mm (10.59 in) ----
I.D. mark (Pink/3) 263.5 mm (10.37 in) 260.5 mm (10.26 in) ----

2-9
MAINTENANCE SPECIFICATIONS
Preload length
1.5–13 mm (0.06–0.51
in)←
Spring rate, STD K = 54.0 N/mm (5.50 kg/
mm, 308.0 lb/in)←----
Optional spring Yes←----
Enclosed gas pressure 1,000 kPa (10 kg/cm
2,
142 psi)←----
*Spring specification varies according to the differ-
ence in the production lot.
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04
in)
Wheel:
Front wheel type Spoke wheel ----
Rear wheel type Spoke wheel ----
Front rim size/material 21 × 1.60/Aluminum ----
Rear rim size/material 19 × 2.15/Aluminum ----
Rim runout limit:
Radial ---- 2.0 mm (0.08
in)
Lateral ---- 2.0 mm (0.08
in)
Drive chain:
Type/manufacturer DID520DMA2 SDH/DAIDO ----
Number of links 113 links + joint ----
Chain slack 50–60 mm (2.0–2.4 in) ----
Chain length (15 links) ---- 242.9 mm
(9.563 in)
Front disc brake:
Disc outside dia.×Thickness 250 × 3.0 mm (9.84 × 0.12 in) 250 × 2.5 mm
(9.84 × 0.10 in)
Pad thickness 4.4 mm (0.17 in) 1.0 mm (0.04
in)
Master cylinder inside dia. 9.52 mm (0.375 in) ----
Caliper cylinder inside dia. 22.65 mm (0.892 in) × 2 ----
Brake fluid type DOT #4 ----
Rear disc brake:
Disc outside dia.×Thickness 245 × 4.0 mm (9.65 × 0.16 in) 245 × 3.5 mm
(9.65 × 0.14 in)
Deflection limit ---- 0.15 mm
(0.006 in)
Pad thickness 6.4 mm (0.25 in) 1.0 mm (0.04
in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 25.4 mm (1.000 in) × 1 ----
Brake fluid type DOT #4 ----Item Standard Limit

2-10
TIGHTENING TORQUES
ELECTRICAL
TIGHTENING TORQUES
ENGINE
△- marked portion shall be checked for torque tightening after break-in or before each race.
Brake lever and brake pedal:
Brake lever position 95 mm (3.74 in) ----
Brake pedal height (vertical height above footrest
top)5 mm (0.20 in) ----
Clutch lever free play (lever end) 7–12 mm (0.28–0.47 in) ----
Throttle grip free play 3–5 mm (0.12–0.20 in) ----Item Standard Limit
Item Standard Limit
Ignition system:
Advancer type Electrical ----
CDI:
Magneto-model (stator)/manufacturer 2S210/YAMAHA ----
Charging coil 1 resistance (color) 720–1,080 Ωat 20 °C (68 °F) (Green–
Brown)----
Charging coil 2 resistance (color) 44–66 Ωat 20 °C (68 °F) (Black–Pink) ----
Pickup coil resistance (color) 248–372 Ωat 20 °C (68 °F) (White–Red) ----
CDI unit-model/manufacturer 34P-00/YAMAHA (USA and CDN) ----
34P-10/YAMAHA (Except for USA and
CDN)----
Ignition coil:
Model/manufacturer 5TA-10/DENSO ----
Minimum spark gap 6 mm (0.24 in) ----
Primary coil resistance 0.08–0.10 Ωat 20 °C (68 °F) ----
Secondary coil resistance 4.6–6.8 kΩat 20 °C (68 °F) ----
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 14 1.4 10