First gen. uses 3 wires 1977 B1 standard...3phase excited field 1977 C1 custom.....3phase excited field Second gen. uses 2 wires 12 pole stator and rotor 1978 B2 standard...1phase permanent mag 1978 C2 custom.....1phase permanent mag 1978 D1 sr.........1phase permanent mag 1979 B3 standard...1phase permanent mag 1979 C3 custom.....1phase permanent mag 1979 D2 sr.........1phase permanent mag 1980 E1 LTD........1phase permanent mag 1980 F1 custom.....1phase permanent mag 1980 B4 standard...1phase permanent mag 1980 C4 custom.....1phase permanent mag 1980 D3 sr.........1phase permanent mag Third gen. uses 3 wires 18 pole stator and rotor 1981 D4 sr..............3phase permanent mag 1981 F2 ................3phase permanent mag 1982 F3 ................3phase permanent mag 1983 F4 ................3phase permanent mag 1981 H1 csr.............3phase permanent mag 1982 H2 csr.............3phase permanent mag 1983 H3 csr.............3phase permanent mag up to KZ650DE052650 Fourth gen. 1983 H3 csr.............New type 3phase permanent mag starting at KZ650DE052651