Even in a car, it does NOT need to be securely encased. This is simply to avoid having it concealed. In a car or on a motorcycle, if you don't have a permit, keep it unloaded and in plain view. If you have a permit, none of this matters.
Welcome to OCDO!
76-10-502. When weapon deemed loaded.
(1) For the purpose of this chapter, any pistol, revolver, shotgun, rifle, or other weapon described in this part shall be deemed to be loaded when there is an unexpended cartridge, shell, or projectile in the firing position.
(2) Pistols and revolvers shall also be deemed to be loaded when an unexpended cartridge, shell, or projectile is in a position whereby the manual operation of any mechanism once would cause the unexpended cartridge, shell, or projectile to be fired.
(3) A muzzle loading firearm shall be deemed to be loaded when it is capped or primed and has a powder charge and ball or shot in the barrel or cylinders.