Extending immediately below the camshaft is another vertical shaft, driven by bevel gears from the crank-shaft, and terminating in a worm which drives the multiple piston oil pumps. - A History of Aeronautics
For maximum power, the solenoid valve is always closed and full valve opening is achieved following completely the mechanical camshaft, which is specifically designed to maximise power at high engine speed (long opening time). - gizmag Emerging Technology Magazine
The overhead valves (one intake and one exhaust for each cylinder) are operated by pushrods and rockers from the camshaft, which is mounted in four bearings in the crankcase.
You probably won’t want to break down the engine to see if the camshaft is a few too many thousandths worn from driving lifter number seven. - The RVer’s Bible
The engine also has a sportbike-derived chain-and-gear camshaft drive system that allows for a short/narrow cylinder head design and reduced overall engine height. - Quad 2009 ATV Buyers Guide