From Consumer Wiki
A city or county may adopt a bicycle licensing ordinance or resolution stating that no resident shall operate any bicycle on any street, road, highway, or other public property within the city or county, unless such bicycle is licensed. The Department of Motor Vehicles (DMV) is the licensing authority.
Consumers should check with the local police department for bicycle registration, licensing, and regulations in their area.
City of Sacramento Code Enforcement Office
1231 I Street
Sacramento, CA 95814
See also: Article 4, Chapter 1, Division 11 of the California Vehicle Code and Division 16.7 of the California Vehicle Code