It might help note what throttle habits the OP relyes on most. Then consider avg mi. because the harder you twist the throttle, the worst your mi. will be
Then consider what your ecm has learned and there you have it. Same fill. Lower range estemates

 

Oh.. my... goddd.. I just about fell out my chair!

 

Trade her for a Victory so you get what you pay for please

 

There has been several times I have pulled in to fill up and it took over 4.5 gallons to fill up with my 2016 Heritage.

It seems my low fuel warning is off by about 10-15 miles but one time, it was dead on! I look at is as I better not procrastinate in looking for gas when the low fuel light comes on.

I am averaging about 45 MPG for the 2016.

 

All estimates chief! If the light comes on get gas. If it doesn't, don't get gas. I rely on trip miles since I know the range and fuel light are estimates.

 

I consider my self lucky, that even tho I added a tank lift. I still add 4gal. at each fill. And I only ride one speed. Faster

 

I have a 2017 Heritage and yes it has a 5 gallon tank. I've had mine back to the dealer for fuel gauge issues and they replaced the speedometer head twice and the sending unit once. I was told by the dealer, that according to Harley Davidson, a fuel gauge can be off by as much as a quarter of a tank and be considered within specifications. I was told that if I had any further questions regarding the fuel gauge I should contact Harley Davidson directly. I gassed up yesterday with the gauge reading a quarter of a tank and it only took 2.6 gallons and I got 42 mpg. If you do the math, it should have taken 3.75 gallons at a quarter tank on the gauge. I don't know if you can adjust the float level but I was told to live with it.

 

 

I can't believe this thread as this is one of the top stupidest things I've ever read. Not only can the gauge be off or the level armo, if the bike is lowered it will not read correctly if the tank is lifted it will not read correctly. It's a 5 gallon tank figure it out by filling the tank, run it low, fill it back up and divide the miles by the gallons filled and you will get your miles per gallons. Multiply by 5 and that is your range. Set at 0 every fill and use your odometer to figure out if you have gas left.