It was much easier back then when the bikes had 5 digits instead of 8.
00001-09999 were 1st generation 3-speeds
10000-13999 were 2nd generation 3-speeds
14000-19999 are continuous gear
20000-29999 were 2nd generation 3-speeds
30000-35999 are continuous gear
36000-38999 were 1st generation electric
40000-44999 are continuous gear
50000-77999 are continuous gear
78000-83999 were 1st generation electric
84000-87999 are continuous gear
J9000--series were 2nd generation 3-speeds