A camshaft is a cylindrical rod with lobes on it. These lobes are used to push on the valves in the cylinder head, opening and closing them. The camshaft is driven by the engine's crankshaft through a timing belt or chain.
In an air-cooled OHC engine, the cylinder head is exposed to the air for cooling. This means that the engine does not need a radiator or coolant, which makes it lighter and more compact. Air-cooled OHC engines are also more efficient than liquid-cooled engines because they do not lose any of their energy to the coolant.
However, air-cooled OHC engines can also be more noisy than liquid-cooled engines. This is because the air passing over the cylinder head creates noise. Air-cooled OHC engines also require more frequent oil changes than liquid-cooled engines because the oil is used to help cool the engine.
Overall, air-cooled OHC engines are a good option for small engines that need to be lightweight and efficient. However, they can be noisy and require more frequent oil changes.
