I'm getting pretty much the same results on my 2014 XL1200cp 4.5 gal tank.

In another thread there was a discussion about the fuel pump that is located inside the tank of Harleys.

One poster listed the dimensions of the fuel pump. When those dimensions were converted to gallons, it translated to exactly 1/2 gallon.

Therefore, my 4.5 gallon tank is actually a 4.0 gallon. Knowing this, it corresponds pretty closely to what I see at the pump after the light comes on.

DON

 

Sounds like its all over the board and each bike is slightly different. I'll gas up around 100 miles cause it seems like after my light comes on I still got 1.5 gallons to go. Thanks for the feedback from everyone! Love this Forum, always get great advice and answers.

 

I have a 3" tank lift on my Sporty...light comes on with about a gallon left. As stated, each bike is a bit different, how we ride tank to tank can be different also, so take that into account when using a trip meter.

I have filled my 3.3 gallon tank up with 3.3 gallons a few times...yeah, it was spitting and sputtering on fumes each time.

I have also filled up my touring 6 gallon tank with 6.04 gallons, and it was NOT sputtering.

Here's a thread with a lot more info on the subject of gauges, idiot lights and so on.

https://www.hdforums.com/forum/vendo...ed-weekly.html

 

Harley say's it's a 4.5 gal tank So it should hold 4.5gal Other wise they would have to call it a 4.0gal tank. I'm not saying your wrong I'm but I am hoping your wrong. LOL .
I would love to drain my tank and fill it at the gas station and find out. It may end up being one the 8 wonders of the world.

I looked at my log book (ya i keep a gas milage log old airplane habit) and the most I ever put in was 3.2gal so did I really have 1.3 gal left in the tank?

 

That's wishful thinking at best. With how motorcycle tanks sit at an angle and so forth you'll never get one completely full. My tank is rated 3.3 gallons. If I'm lucky, I MAY have 3 gallons in a full tank.

 

Three comments! One is that tank capacity is only approximate, so we should take what it says in the manual with a pinch of salt. The other is that many of us, having read umpteen threads in HDF on the subject, don't investigate the lower reaches of our tanks, after the warning light comes on. Finally, it isn't wise to ride until the last drop is used up!

 

My Nightster's light would come on at around 90 miles, with one and a third gallon remaining. Once, while riding the freeway through an area with abundant filling stations, I pushed it to 130 or so miles, until it began to sputter: it took three gallons.

 

When it starts sputtering its time!

 

While I agree that the tank capacity is not exact, I have never seen a 3.3, 5 or 6 gallon tank that did not actually hold at least the amount of fuel specified. The tanks hold at least as much fuel as specified After all the innards (fuel pump) are installed.

The low fuel indicator light is a type of electronic reserve, and it varies a lot on when it will come on.

While there is a common belief (that may be true) that you should not run an EFI bike til it sputters, I have done it many times.

Below is a picture of a 6 gallon tank that was just filled up. It was NOT sputtering before fill-up, AND it has a 1.5" Tank Lift with the Deluxe Option installed.



Yes, I know that gas pumps can also vary in what they read...but I have done this numerous times on Sportys, Dynas and Touring bikes.

If you really want to know what the true usable capacity is of your tank, when you are getting "low", ride until it starts sputtering in an area that is abundant in gas stations. After it is sputtering, pull in and fill up to the splash guard. Make sure you are on level ground (or headed slightly downhill) when you fill up. Then you will know.

 

With any system that uses an electric fuel pump be your car, bike, whatever, the principle to keep in mind is to prevent premature failure of the pump is to not run it dry. The only thing keeping the pump cool is the fuel. As fuel reaches a certain level the pump will run hotter. Always a good idea to keep things no less than 1/4 tank. The sputtering is just the pump itself struggling to keep fuel supply running through it constant. Make for a good myth busters episode.