43 C.F.R. § 420.11

Each off-road vehicle that is operated on Reclamation lands shall meet the following requirements:

(a) It shall conform to applicable State laws and vehicle registration requirements.

(b) It shall be equipped with a proper muffler and spark arrestor in good working order and in constant operation. The spark arrestor must conform to Forest Service Spark Arrestor Standard 5100-1a, and there shall be no muffler cutout, bypass, or similar device.

(c) It shall have adequate brakes and, for operation from dusk to dawn, working headlights and taillights.