41-13-209. Overpowered watercraft prohibited; horsepower rating plates; mufflers required. (a) No watercraft shall be equipped with any motor or other propulsion machinery that has a horsepower rating exceeding the maximum stated on the capacity plate approved and issued by the United States coast guard and affixed to the watercraft by the manufacturer. (b) Motorboats shall be equipped, maintained and operated to prevent excessive or unusually loud noise and shall at all times be equipped with a muffler or shall use another method of noise suppression in good working order and in constant operation. No person shall operate or allow the operation of any motorboat equipped with an altered muffler or muffler cutout, bypass or other devise designed or installed to continually or intermittently bypass or otherwise reduce or eliminate the effectiveness of any muffler or muffler system. (c) Subsection (b) of this section shall not apply to motorboats competing in or while on trials of an approved race or regatta nor in areas designated by the game and fish department.
Wyoming Legal Code