Section R. 281.516 - Weight capacityRule 6.
(1) The capacity tag shall contain the weight capacity of the watercraft determined as hereinafter provided.(2) The weight capacity of a watercraft for use with an outboard motor, except a watercraft dependent solely upon the buoyancy of pontoons or similar flotation devices, shall be determined by either of the following methods: (a) The formula WC=7 1/2 LBD, where WC is the weight capacity in pounds, L is the centerline length, B is the maximum beam amidships, and D is the effective depth figured from keel to lowest freeboard.(b) Reference to the manufacturer's capacity tag installed in a watercraft if manufactured or offered for original sale in this state on or after January 1, 1968, or in accordance with standards approved by the state waterways commission.(3) The weight capacity of a watercraft with a permanently installed engine, except watercraft dependent solely upon the buoyancy of pontoons or similar flotation devices, shall be determined in the same manner as for watercraft for use with outboard motors, except that the weight of all machinery and associated operating gear including battery, fuel, and fuel system shall be subtracted.(4) The weight capacity of a watercraft dependent solely upon the buoyancy of pontoons or similar flotation devices shall be determined by applying the formula WC=[(62 1/2V)--Boat Wgt.] : 2, where WC is the weight capacity of the watercraft, and V is the volume of both pontoons. If equipped with a permanently installed engine, the weight of all machinery and associated operating gear including battery, fuel, and fuel system shall be subtracted from the weight capacity.(5) The weight capacity of a rowboat and any other watercraft for use without an outboard motor shall be determined in the same manner as for a watercraft for use with an outboard motor, following the formula expressed as WC=7 1/2 LBD.(6) The weight capacity of a canoe shall be determined by the formula WC=7 1/2 LBD x 2.(7) The livery operator shall provide the inspecting officer with information relative to the weight of the watercraft either by reference to the manufacturer's rating or by actual weighing of the watercraft.Mich. Admin. Code R. 281.516