The level in the tank on most all Rockets is not adjusted properly. You have to take the fuel pump/float assembly out of the tank and adjust the float arm.
For me, it's not worth the effort, unless you are doing something else. I've always used my trip meter for fuel anyways. I had mine about right last year when I was doing some other work, and then I took it to the dealer ( who was a great help other than this tidbit) who removed the fuel pump assembly to change the fuel filter, and when they put it back together, now my fuel light is on all the time, which means the float arm is stuck down... Some day I will fix it, but don't know when that will be.. lol
You could take it to the dealer and see if they will adjust it under warranty..? Or have them check it at the next service...