What is a motorcycle?This seems to indicate that he does need the endorsement.
A motorcycle is a vehicle whose motor displaces more than 150 cubic centimeters and has a seat or saddle for the use of the rider. It is designed to travel on not more than three wheels in contact with the ground and weighs less than 1,500 pounds.
Class C -You may operate a motorcycle with a sidecar attached, a three-wheel motorcycle, or a motorized scooter.A Class C California Driver's License is the normal license that you get when you move there.
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