Vehicle Code § 27800
ARTICLE 7. Motorcycles
It is unlawful for a driver of a motorcycle or a motorized bicycle to carry any other person thereon, except on a seat securely fastened to the machine at the rear of the driver and provided with footrests, or in a sidecar attached to a motorcycle and designed for the purpose of carrying a passenger. Every passenger on a motorcycle or a motorized bicycle shall keep his feet on the footrests while such vehicle is in motion.