A sample from the products for the Shift Cam - Fork include: Ball, Lever, Shift 4, Shift Shaft Assy, Spring, Torsion(3fa).
This Shift Cam - Fork diagram displays the required parts for the Yfa1b Breeze Moto-4 1991 Shift Cam - Fork.
In this schematic the "Circlip(58y)" is used most often.