To some extent, this may be due to the shape of the tank itself, as in cars/trucks, different levels of fill will be used up at different rates because the tanks have to be formed to fit the irregular areas they have to fit in. They generally aren't that nice uniformly shaped container like your gas can.
If the tank is thin and narrow at the top and bigger on the bottom, it will seem like the quad is burning gas like a hog since the gas level will fall rapidly at first and then last a long time at the bottom of the guage reading. It will even seem worse if you never let the tank get under 1/2 to 1/4 full since most of your fuel volume is at the bottom of the tank.
If the tank is big on top, small on the bottom, just the opposite will be true and you may be tricked into thinking the guage never moves...
Thus the results of Capers experiment!

 

I just think the guage is not right up to the top of the tank!!!..........My tank shows full ....but will still take a gallon of gas!!.........On a 16 liter tank 4-5 liters.....is alot 1/4 of the whole tank........So my tanks drops about 1/4 before the guage moves.........The tank's shape is not that different in THIS case...Correct?......................I do see what your sauing though!!.......Polaris was just PLAIN off in reading the top part of these tanks!!............Caper..

 

Caper, I would think that all full size Sportsmans should have a very similar tank for the last few model years anyway, so if what I am saying is at least some of the problem, the guages would read somewhat the same...is this the case, or do different owners report different results? If results vary a lot, that would shoot my therory in the butt!

Do the 450/500 models share the same tank with the bigger 700/800s? Do the twin engines change the fit of the tanks?

PS...Did someone say something about TOAST? LOL! Sorry, there I go again!

 

I read on here some of the bigger Polaris Quads ....have smaller tanks........We need to start a new post just to see the size of riders tanks/with cc size motors!!.........Go ahead start one and lets see!!....Caper.......

 

'07 700 EFI...... My fuel guage works perfecty....Top bar lights up when full, guage drops with fuel level as it should. It reads full for the first 1/2 gallon or so because the sender in the tank doesn't read to the absolute top of the tank, but this is normal. I bought this machine brand new in August, and it now has about 200 miles on it. It's been flawless so far. My only comlaint right from the get go was the excessive clunking/ drivetrain noise that is heard when slowing down and coasting at low speed on a trail. But I guess this is normal. But thats a different story....sorry for getting off topic.....

 

When I took my complaint to the dealer before the warranty expired, he checked it and said it was fine. It's apparently the nature of the beast, at least mine, that the tank has to get half empty before the indicator moves off of "full". Even riding all day, mine never gets off of "full", and I end up having to put in 2-1/2 gallons. With a six gallon tank, though, so what? As long as I fill up every day, it doesn't matter, or at least that's what I've rationalized.

 

<div class="FTQUOTE"><begin quote>Originally posted by: GuitarPicker

When I took my complaint to the dealer before the warranty expired, he checked it and said it was fine. It's apparently the nature of the beast, at least mine, that the tank has to get half empty before the indicator moves off of "full". Even riding all day, mine never gets off of "full", and I end up having to put in 2-1/2 gallons. With a six gallon tank, though, so what? As long as I fill up every day, it doesn't matter, or at least that's what I've rationalized.</end quote></div>

An inoperable gauge is not the nature of the beast, and is not kosher at all.
I've got a 07 Sportsman 500 that never shows anything but full.

Does anybody have a service manual for a Polaris with the electric fuel gauge?
Can you tell me what the resistance (Ohm) range is for the gauge. I wanna put my meter on mine to see if it's the gauge itself or if the problem's in the instrument cluster itself.

 

This is for a 2006 Sp 450/500 .....

Hook a Ohmmeter up to the Brown& purple wire and White wire..

With the sender float in the empty position the meter should read 5 Ohms
Now slowly lift the sender float to the full position now it should read 90 Ohms.
If the readings are not between 5-90 Ohms replace the Fuel sender.

Remember this is for 2006 Sportsman 450/500cc
Yours may or may NOT be the same........Hope that helps you out !!..Caper.......

 

I know I already posted a reply but it's not here. I don't know if it was another thread on this or not. Anyway...

My gauge on my 2006 SP500 worked great until it was hotwired and stolen. After I got it back and the wiring harness was replaced, it read full all the time, even when it was clearly half empty. The dealer took the sending unit out, looked at it and saw nothing wrong and put it back in. It worked fine again after that. I think the float stuck at the top when I filled the tank. If it happens again I'm just going to whack the side of the tank with a rubber mallet and see if the stuck float falls down to where it's supposed to be.