Yamaha YFM25RY Automobile User Manual


 
ENGINE SPECIFICATIONS
2-4
EAS29120
ENGINE SPECIFICATIONS
Cylinder head
Volume 20.50–21.50 cm
3
(1.25–1.31 cu.in)
Warpage limit 0.05 mm (0.0020 in)
Cylinder
Bore 74.000–74.016 mm (2.9134–2.9140 in)
Wear limit 74.100 mm (2.9173 in)
Camshaft
Drive system Chain drive (right)
Camshaft lobe dimensions
Intake A 36.890–36.990 mm (1.4524–1.4563 in)
Limit 36.790 mm (1.4484 in)
Intake B 30.111–30.211 mm (1.1855–1.1894 in)
Limit 30.011 mm (1.1815 in)
Exhaust A 36.891–36.991 mm (1.4524–1.4563 in)
Limit 36.791 mm (1.4485 in)
Exhaust B 30.092–30.192 mm (1.1847–1.1887 in)
Limit 29.992 mm (1.1808 in)
Camshaft runout limit 0.030 mm (0.0012 in)
Timing chain
Model/number of links DID SCR-0404 SV/104
Tensioning system Automatic
Rocker arm/rocker arm shaft
Rocker arm inside diameter 12.000–12.018 mm (0.4724–0.4731 in)
Limit 12.036 mm (0.4739 in)
Rocker arm shaft outside diameter 11.981–11.991 mm (0.4717–0.4721 in)
Limit 11.950 mm (0.4705 in)
Rocker-arm-to-rocker-arm-shaft clearance 0.009–0.037 mm (0.0004–0.0015 in)