Check out any of the thirty-one Carburetor (component Parts) components enlisted.
In this schematic the "Screw-washer,4x14" is used most often.
Parts such as the Carburetor (component Parts): Screw-wash4x18, Jet,slow #35, Needle Set,jet, Top are included in the Gl1500c Valkyrie 1999 (x) Canada / Rbm Carburetor (component Parts) parts fiche.