Mont. Code Ann. § 61-8-603
61-8-603 Riding on bicycles, mopeds, or motorized scooters
61-8-603 . Riding on bicycles, mopeds, or motorized scooters. A person propelling a bicycle or moped may ride only on or astride a permanent and regular seat attached to the bicycle or moped. This requirement does not apply to a motorized scooter.