Check your gauge against what you can actually put in the tank. I was awfully disappointed at the mileage my new '13 was getting compared to the old '05 until I tried a test, I rode it until the last gauge segment was blinking reliably, which should be fuel pump riskin' low on gas. Then took it to the gas station. I found that I was able to put just barely 13 liters into the tank, four short of its 17 liter capacity.
About an American gallon was still left in my 'empty' gas tank! Almost a quarter of its capacity.
It explained why my new quads gauge lost the first of six blocks in only 25 kilometers or so, far sooner than I was accustomed to.
Obviously the long float wire on the sending unit in the new ones gas tank has a different bend.
If your gauge is coming off 'full' in just 15 or 20 miles, get suspicious. You may be getting better mileage than you are being told.
