Every person riding a bicycle upon a roadway shall be granted all of the rights and shall be subject to all of the duties applicable to the driver of a vehicle by the laws of the State declaring rules of the road applicable to vehicles or by the traffic code of the City applicable to the driver of a vehicle, except as to those provisions which by their nature can have no application. Whenever such person dismounts from a bicycle the person shall be subject to all regulations applicable to pedestrians.
(Code of Iowa, Sec. 321.234)