Royal Enfield

01 Engine

The crankcase was made up of vertically-split, aluminium castings. Two roller bearings supported the built-up crank, with heavy flywheels having an 85mm throw. The flywheels contained the ‘knife and fork’ con rod arrangement which also had roller bearing big-ends. The barrels were of cast iron, the 85.5mm bore resulting in the 976cc capacity. The detachable cylinder heads were also cast iron. A single camshaft operated the side-valves via finger followers and the valve gear was enclosed, although the flimsy cover was not notably oil-tight.