COLORADO

State registration of motorcycles began at the same time as automobile registration on July 15, 1913.  The main difference was that motorcycle owners were required to provide their own rear plate, instead of being assigned a state-issued plate in 1913 and 1914.  We surmise that motorcycle owners were assigned the same number in 1914 as they had been issued in 1913, so that they wouldn't need to make a new plate.  There were 2,753 motorcycle registrations in 1913 and 3,683 in 1914.  The highest state pre-state motorcycle plate known is #3280.  Motorcycle dealers were required to register in the same manner as dealers, and therefore are not expected to have been assigned state-issued plates until 1915.

State-issued motorcycle plates began in 1915, and motorcycle dealer plates are reported to have also begun at this time.  An unusual aspect of 1915 motorcycle plates is that they were made of embossed steel rather than the porcelain used for all other 1915 plates.  There were 4,268 motorcycles registered in 1915.  The highest 1915 motorcycle plate known is #4122, and the earliest verified motorcycle dealer plate known is 1916 #D199.

Prior to the state law of 1913, some cities included motorcycles in their motor vehicle ordinances.  The earliest known of these, Colorado Springs, registered motorcycles along with all other motor vehicles from the very first ordinance passed on August 17, 1903.