Missouri Revised Statutes Title XIX. Motor Vehicles, Watercraft and Aviation § 301.070. Computation of fees

1. In determining fees based on the horsepower of vehicles propelled by internal combustion engines, the horsepower shall be computed and recorded upon the following formula established by the National Automobile Chamber of Commerce: Square the bore of the cylinder in inches multiplied by the number of cylinders, divided by two and one-half.

2. The horsepower of all motor vehicles propelled by steam may be accepted as rated by the manufacturers thereof, or may be determined in accordance with regulations promulgated by the director.

3. The horsepower of all motor vehicles, except commercial motor vehicles, propelled by electric power, shall be rated as being between twelve and twenty-four horsepower.

4. Fees of commercial motor vehicles, other than passenger-carrying commercial motor vehicles, shall be based on the gross weight of the vehicle or any combination of vehicles and the maximum load to be carried at any one time during the license period, except the fee for a wrecker, tow truck, rollback or car carrier used in a towing service shall be based on the empty weight of such vehicle fully equipped for the recovery or towing of vehicles.

5. The decision of the director as to the type of motor vehicles and their classification for the purpose of registration and the computation of fees therefor shall be final and conclusive.