Those actions are enough to make an arrest/give a warning, but the story is not. It is a 'he said, she said' thing, unless the dad and brother saw it as well. Even then, independent witnesses or cameras are the real deal breaker.  However, defending yourself is the real key. Why would a stick thrown on the sidewalk hurt a motorcycle unless the motorcycle was on the sidewalk? Dodge softly, and swing a big (shitlord) stick, just like Ole President Polk used ta say, OP.