Motorcycle.com

One habit that most motorcyclists pick up is “the wave”: the simple gesture of recognition you give when you encounter another rider approaching. It doesn’t matter if it’s a total stranger, as long as they’re riding on two wheels, you lift your clutch hand and recognize your shared camaraderie.

Or in this rider’s case, you raise your left paw. Sweets the English bulldog knows the code, recognizing another rider’s wave and returning one of her own.