No person shall drive or operate a motor vehicle on any street within the corporate limits of the city at a rate of speed greater than twenty five (25) miles per hour or on any alley within the corporate limits of the city at a rate of speed greater than ten (10) miles per hour; the above speed limits will govern except where speed limitations have been posted upon the order of the mayor and council. (1974 Code § 7-103; amd. 2010 Code)