Nothing in this article shall be construed to prohibit more than one (1) motorcycle from occupying any parking space as provided by this article, provided that no motorcycle shall be parked in such a manner so as to prevent another from moving away, and provided further that, each owner or operator of such vehicles shall be equally and separately liable for the penalties provided in this chapter if said vehicles are parked after the parking time for the adjacent parking meter for that space has expired. (1978 L.M.C., ch. 7, § 2.)