Which of the following is a legal requirement for riding motorcycles in Idaho?

Possessing a valid driver's license with a motorcycle endorsement is a legal requirement for riding motorcycles in Idaho. This endorsement signifies that the rider has completed the necessary training and understands the specific skills and safety measures needed to operate a motorcycle safely. The requirement ensures that all motorcycle operators are knowledgeable about the rules of the road, risk management, and how to maneuver two-wheeled vehicles effectively.

While wearing sunglasses, having a passenger permit, and carrying a toolkit might enhance the riding experience or improve safety, they are not mandatory legal requirements for operating a motorcycle in Idaho. Therefore, the emphasis on possessing a motorcycle endorsement illustrates the state's commitment to rider safety and proper certification.