The main body of the camshaft is a cylindrical rod with approximately the same length as the cylinder group. There are several cams on it to drive the valve. The camshaft is supported by the camshaft journal in the camshaft bearing hole, so the number of camshaft journals is an important factor affecting the stiffness of the camshaft. If the camshaft has insufficient rigidity, it will bend and deform during operation, which will affect the timing of the gas distribution.
The side of the cam is egg-shaped. The purpose of its design is to ensure adequate intake and exhaust of the cylinder. In addition, considering the durability of the engine and the smoothness of operation, the valve should not have too much impact due to the acceleration and deceleration process in the opening and closing action, otherwise it will cause serious valve wear, increased noise or other serious consequences. Therefore, the cam has a direct relationship with the engine's power, torque output, and smooth running.