Hawaii Revised Statutes Division 1. Government § 291C-53

(a) The director of transportation by rules adopted in accordance with chapter 91, and the counties by ordinance, may regulate or prohibit the use of any controlled-access roadway or highway within their respective jurisdictions by any class or kind of traffic which is found to be incompatible with the normal and safe movement of traffic. Persons operating motorcycles which are otherwise permitted on a controlled-access roadway or highway shall be permitted to use any high occupancy vehicle lane designated on such roadway or highway. For the purposes of this subsection, “high occupancy vehicle lane” means a designated lane of a laned roadway where the use of such designated lane is restricted to vehicles carrying at least the minimum number of persons designated by the director of transportation as indicated on official signs and other official traffic-control devices, and to other vehicles as provided by rules adopted in accordance with chapter 91, or by county ordinance. Notwithstanding any law to the contrary, no person shall operate a neighborhood electric vehicle on any controlled-access roadway or highway.

(b) The director of transportation or a county adopting any such prohibition shall erect and maintain official traffic-control devices on the controlled-access roadway or highway on which such prohibitions are applicable and when in place no person shall disobey the restrictions stated on such devices.