I have never put more that 4.9 or so gallons of fuel in my FLRT. If I run it until the "distance to empty" is down to zero miles I can get just under 5 gallons in it (topping off completely). The specification for the bike is a 6 gallon capacity, so there is always a minimum of 1 gallon in the tank.
Also, my gauge needle does not go all the way to full when the tank is brimmed. I mentioned this at the 1000 mile service and of course was told it was "normal".
Is this common or is your experience different?