Pennsylvania law requires riders to wear a helmet if they: Have not yet turned 21 Do not have at least two years of motorcycle-riding experience Pennsylvania riders can forego the experience requirement if they have taken a motorcycle safety course that allows them to receive clear instructions about how to stay safe out on the road. However, the fact that Pennsylvania law does not require riders to wear motorcycle helmets does not necessarily mean that riders should not wear a helmet. Motorcycle helmets have a 67 percent effectiveness rate for preventing traumatic brain injury. Failure to wear a motorcycle helmet may substantially increase the risk of injury in an accident. It may lead to more serious injury when the rider fails to wear a helmet.