I have a 1996 ohv sport and I get 245 miles to the tank. I have a 14 gallon tank, so that roughly about 17 miles gallon.
Jeeeez.........that’s no way to calculate miles per gallon.
I'm NOT trying to make fun of you, though it always throws me, when I hear guys talk about their MPG based on how many miles they went on a tank full of gas.
FYI, try calculating your MPG the "old fashion way."
There is going to be some variance, though I did say it was the "old fashion way." Start by filling up your gas tank, fully.......on level ground........first click off (second click off or whatever) or until you see the gas is it at a certain level in the filler neck (some stations will not let you look some won't).........sometimes you'll have to wait a little for the gas to settle in the tank........or the tank to "burrrp." You don't need to record how many gallons were needed (this time). Though you must record your odometer reading (or set the trip odometer) and remember this fill up procedure.
Any way..........now, drive it...........fill it when needed (don't have to be exact about filling it), log the number of gallons that went in.............drive it some more...............fill it when needed…………………………always logging the amount of gallons that went in............repeat the procedure several times.
After a couple of cycles: of driving, and filling, and logging the number of gallons...........this last time, you're gonna go to the same gas station and follow the same procedure that you used to fill your gas tank the first time that you started your quest for truth. Record this last odometer reading.
So, all done filling her up..............how many gallons was it this time? OK, now add up all of the gallons since you first recorded the odometer. So, how many gallons was the total?
Now, take the beginning odometer reading and minus it from the ending odometer reading………………this number is the total number of miles that you've traveled.
One more calculation left..............now, divide the number of miles by the number of gallons you used..................that number, is your MPG. Use a calculator, if you have trouble.
Now, like I said it's the "old fashion way"............and this method doesn't take into account for an odometer that is not functioning correctly.
As for computers...............well, perhaps one day................I'll have more faith in them.................and, that includes the GPS method. I've been off roading, when I was actually on a paved street.............at least that is what the GPS map said, I was doing........LOL.
Aloha, Mark