Although your tank has the capacity to hold in excess of 4 gallons, the positioning of the fill port and the position of the motorcycle when on the side stand will prevent you from ever filling the tank to its fullest capacity. And, as Martha Stewart would say, "That's a good thing." This prevents you from over filling and sending the excess into the vent pipes, onto the ground and causing you potential slip, fall, and fire hazards. If its running ok don't worry about how much went in. There are too many variables.
