I have an 09 Heritage and it gets 40 mpg which would mean about 200 miles per tank. The light on mine comes on with 1 gallon of fuel left, so something is definitely wrong with your mpg figure.
Or his light. I have a buddy who's light comes on with around 10 miles til empty. When he says "take the next exit", he ain't kidding.
Mine has more than a gallon left when my light comes on.
You can't judge your mileage by that light. Get to know your bike and when the light comes on. You KNOW how much fuel the tank holds. How much did it take to fill it up? Knowing that number tells you how much you had left when it came on.
And yes, riding into the wind makes a big difference in mileage.
My 04 FLSTCI gets to about 150 and the light comes on, at that point I can only squeeze 3.5 or so in the tank, so it is a bit early, I figure 200 is safe. About 45-50 depending on my wrist.
Ya something must be wrong if my light came on at 90 miles then, maybe no baffles is making my fuel injected bike use so much gas??? I will be putting my brothers old Thunderheader on soon.
.....04 Deuce,95" Stage II,holds 4.9 gal.....light comes on w/1 gal left('sposedly)....if I ride it like I got some sense,(which ain' often)can push 200...however....I'm usually look'n at 'bout 180 or sooner......usually run the big slabs at 80,turns a lil'over 3000 R's..........