Mine is fairly accurate. It reads past full when full, half tank in the middle, and runs out just short of the end of the red (about as far below the white bars as it goes past them when full). I think the people that assemble the tanks may bend the sending units when getting them into the tanks. The gauge on my Vstrom was pretty wild - but as you filled the tank up it went from skinny, to wide, to skinny, to really wide...