Cam shaft with asymmetric cams

A cam shaft with asymmetric cams comprises a shaft body, an air inlet cam, an air outlet cam and a supporting shaft neck, the outer contour of the air inlet cam and the outer contour of the air outlet cam are each composed of a base circle section, an opening section and a closing section, each opening section and each closing section are each composed of a buffering section and a base section, and each buffering section is composed of a constant acceleration section and a constant speed section; the tail end lift and the tail end speed of the buffer section of the exhaust cam are different in the opening section and the closing section, and the total wrap angles of the buffer section and the basic section of the exhaust cam are the same in the opening section and the closing section. The speed of the exhaust cam at the tail end of the opening buffer section is higher than that of the tail end of the closing buffer section, so that the exhaust valve can be quickly opened at the opening section, the speed is r