Geki originally came from an ancient prehistoric civilization that coexisted with dinosaurs. Was the adopted prince of the Yamato Tribe and leader of the Zyurangers.
Jason was a high school student and peer coach prior to becoming a Ranger (and during).
Geki was more than 170 million years old.
Jason was very young.
Geki volunteered to go in suspended animation millions of years ago, in case Witch Bandora breaks from her imprisonment. Was awoken by Barza when said scenario happened.
Jason was not aware of Rita Repulsa prior to becoming a Ranger. Was drafted by Zordon when Rita escaped her prison.
Geki was the younger brother of Burai, the Dragon Ranger.