Virtual or online motorcycle games are safe for toddlers to play, but games involving driving a real motorcycle should not involve toddlers. Their bodies are not developed enough to handle the speeds and stresses such games place on the body.
Toddlers should not take part in live motorcycle games because the concepts of safety and rules are not something they can understand at such an early stage of life. The risk of bodily harm is high enough for an adult, and it is exponentially higher for children, especially toddlers. Online games are safer for toddlers because the biggest danger is the potential for the mobile device to overheat.