The main body of the camshaft is a cylindrical rod body approximately the same length as the cylinder block. There are several cams on the top for driving the valves. The camshaft is supported in the camshaft bearing hole through the camshaft journal, so the number of camshaft journals is an important factor affecting the rigidity of the camshaft support. If the camshaft stiffness is insufficient, bending deformation will occur during work, affecting the timing of gas distribution.
The sides of the cam are egg-shaped. The purpose of its design is to ensure sufficient intake and exhaust of the cylinder. In addition, considering the durability of the engine and the smoothness of the operation, the valve should not have too much impact due to the acceleration and deceleration during the opening and closing action, otherwise it will cause severe valve wear, increased noise, or other serious consequences. Therefore, the cam and the engine's power, torque output and smooth running are directly related.