Tom Welling couldn't drive a motorcycle prior to this episode. He needed a stunt double for those scenes.
In the comics, red kryptonite does not have a consistent effect on Superman. Its effects are completely random and sometimes can be positive. Also, generally speaking, whatever effect the red kryptonite has had, it only lasts 24 hours.
This is the first appearance of Clark's Kal personality. Kal stops behaving like a hero and behaves without inhibitions. However, Kal still dutifully goes to school.
John Schneider did his own stunt when thrown against the truck.
Lionel Luthor (John Glover)'s line, "so the son becomes the father" is part of a line spoken by Jor-El in Superman (1978).