One rare illustration of Jiro. From the Ishinomori Shotaro no Fantasy World artbook. It’s probably the last time Ishinomori himself drew the character.
At the time the Kikaider manga series first came around, Ishinomori was overloaded with work. He was rather busy with Sabu and Ichi Detective Tales, Ryu The Primitive boy, 009-1, Sarutobi Ecchan, Shoot! Shoot Shoot! and others. So most of the work in the series was made primarily by his assistants: Hio Akira, Tsuchiyama Yoshiki, Hosoi Yuuji and Yamada Goro. While Ishinomori only did the rough sketches for them to follow. This same technique was used again in the first volume of Japan, Inc and Hokusai (he was starting to go blind around that time).
Despite these issues, Kikaider remained as his favorite hero character. And became one of his most popular creation.