36 C.F.R. § 327.2
Vehicles
(a) This section pertains to all vehicles, including, but not limited to, automobiles, trucks, motorcycles, mini-bikes, snowmobiles, dune buggies, all-terrain vehicles, and trailers, campers, bicycles, or any other such equipment.
(b) Vehicles shall not be parked in violation of posted restrictions and regulations, or in such a manner as to obstruct or impede normal or emergency traffic movement or the parking of other vehicles, create a safety hazard, or endanger any person, property or environmental feature. Vehicles so parked are subject to removal and impoundment at the owner's expense.
(c) The operation and/or parking of a vehicle off authorized roadways is prohibited except at locations and times designated by the District Commander. Taking any vehicle through, around or beyond a restrictive sign, recognizable barricade, fence, or traffic control barrier is prohibited.
(d) Vehicles shall be operated in accordance with posted restrictions and regulations.
(e) No person shall operate any vehicle in a careless, negligent or reckless manner so as to endanger any person, property or environmental feature.
(f) At designated recreation areas, vehicles shall be used only to enter or leave the area or individual sites or facilities unless otherwise posted.
(g) Except as authorized by the District Commander, no person shall operate any motorized vehicle without a proper and effective exhaust muffler as defined by state and local laws, or with an exhaust muffler cutout open, or in any other manner which renders the exhaust muffler ineffective in muffling the sound of engine exhaust.
(h) Vehicles shall be operated in accordance with applicable Federal, state and local laws, which shall be regulated by authorized enforcement officials as prescribed in § 327.26.