Fuel light comes on on my FZ1s at about 120, then the counter zeros itself and i have done about thirty on the reserve counter.
Sometimes light does not come on until 140, and all at good fun speeds.
I think i put about £23.00 in ,cant remeber,,oh and fill it up,,right up.even sit on bike and hold upright,fill to top.Then you will go about 180 to run out,,puuttt puutt pop