Heres a few shots of the sportster's paint scheme. This may have been the 3rd or 4th version of this bike at the time. Hand made sissybar, struts, raked trees, looks like 8" over tubes, and the frame was molded with squared off front legs.
The design on the gas tank came from Rick Griffin's cover for R. Crumb's Zap Comics. See below. He painted it by hand with 1 shot. He changed it up a bit and put the sun running in tennis shoes. Same thing on other side of the tank. On the flat spot of rear fender I believe he had a cartoon hotdog running in sneakers too.