Hi guys, this is what I get on my bike (02 Intruder VS800-3.4 gal tank)
which is the same size as the 1400, on the hwy I get about 35 miles to the gal, that would be about 119 miles to the tank. My bike has 5 speeds and I ride single. That would be the max running the tank empty which I don't recommend. Don't know is this helps but you asked.