Parts such as the Right Knuckle Cover (model K/l/m): Washer (5.5x16x1.2), Nut ,5mm, Nut 6mm, Case Assy,throttle are included in the Rmx250 1989 (k) Usa (e03) Right Knuckle Cover (model K/l/m) parts fiche.
The Screw is the cheapest item from this partsfiche.
In this schematic the "Screw" is used most often.