Hi poo,
mine reads empty also at 200km which is about 130 miles like yourself, but the reserve telling me I have 70km left only comes on after about 270km and I've found that to be pretty accurate, I just put the trip meter on at every fill up to doulbe check the accuracy so as not to run out.
playing around trying to bent floats etc. is pretty hit and miss, and unless there is a way to recalibrate the electronics I think its a waste of time with the distink possibility of braking something.
How many other bikes do you know with a accurate fuel gauge? we have a trip meter that is accurate what els do we need?