Yamaha YZ450FP 2023, Owner'S Service Manual

Page: 49 / 388

ENGINE SPECIFICATIONS
2-4
Friction plate 2 thickness 2.12–2.28 mm (0.083–0.090 in)
Wear limit 2.02 mm (0.080 in)
Plate quantity 4 pcs
Clutch plate 1 thickness 1.35–1.45 mm (0.053–0.057 in)
Plate quantity 7 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch plate 2 thickness 0.93–1.07 mm (0.037–0.042 in)
Plate quantity 2 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch spring free height 5.80 mm (0.228 in)
Clutch spring free height limit 5.51 mm (0.217 in)
Push rod bending limit 0.10 mm (0.004 in)
Drivetrain
Primary reduction ratio 2.481 (67/27)
Transmission type Constant mesh 5-speed
Gear ratio
1st 2.000 (28/14)
2nd 1.625 (26/16)
3rd 1.350 (27/20)
4th 1.136 (25/22)
5th 1.000 (21/21)
Main axle runout limit 0.08 mm (0.0032 in)
Drive axle runout limit 0.08 mm (0.0032 in)
Secondary reduction ratio 3.769 (49/13)
Final drive Chain
Air filter
Air filter element Wet element
Air filter oil grade Yamaha foam air filter oil or other quality foam
air filter oil
Fuel pump
Maximum consumption amperage 2.4 A
Fuel injector
Resistance 12.0

Throttle body
ID mark BHR1
Idling condition
Engine idling speed 1900–2100 r/min
Coolant temperature 70–80

C (158–176

F)
Fuel line pressure (at idle) 300–390 kPa (3.0–3.9 kgf/cm², 43.5–56.6 psi)
Throttle grip free play 3.0–6.0 mm (0.12–0.24 in)