The laws regarding riding a motorcycle without an overshirt, or any specific clothing requirement, can vary from state to state in the United States. Some states have specific regulations related to motorcycle safety gear, while others may not have any requirements beyond wearing a helmet (where applicable).
In general, it is recommended to wear appropriate protective gear, including a helmet, eye protection, long pants, and sturdy footwear when riding a motorcycle, regardless of the legal requirements. Wearing protective clothing can help reduce the risk of injury in the event of an accident.
To know the specific laws regarding clothing requirements for motorcycle riders in your state, you should consult the motorcycle or traffic laws established by your state's Department of Motor Vehicles (DMV) or a local law enforcement agency. They will provide you with accurate and up-to-date information on what is legally required for motorcycle riders in your jurisdiction.