Well, I definitely donít think having it come on when itís half full is normal. I do recall some threads here where you can find about the fuel gauge issues. Look on the search function. Personally, my experience is that moto rule gauges are notoriously incorrect and youíre lucky if they indicate properly. Mine works ok but, I go by mileage. We all know how many miles it can go and when Iím near 100 (160 km) I start looking for gas. I and others have gone to 130 (some even more) but, I donít like the stress of it. Regardless, thereís clearly something amiss with yours and it should be checked.