The ability to balance on a moving motorcycle while standing up and not holding onto anything is highly dependent on several factors, including the rider's skill, experience, physical fitness, the specific motorcycle model, speed, road conditions, and environmental factors such as wind.
Experienced and skilled riders who practice balance and control techniques can stand up on a motorcycle and maintain their balance for short durations. However, it is not safe or recommended to attempt this maneuver while riding on public roads or in traffic.
In controlled environments, such as closed courses or training areas, some riders with advanced skills might be able to maintain balance while standing for several seconds or longer, especially at lower speeds. Advanced riders who participate in motorcycle trials or stunt riding may have greater proficiency in maintaining balance while standing.
It's important to note that standing up on a moving motorcycle without holding onto anything can be extremely dangerous and increases the risk of accidents, loss of control, and injury. Motorcycle riders are strongly advised to ride in a safe and responsible manner, following traffic laws and maintaining both hands on the handlebars for optimal control and safety.