You don't need to know the size of the tank. I found the easiest way to measure the MPG is to:Bateman said:Don't know how big the tank is so no idea of MPG...
fill the tank to the brim,
reset the odometer to zero,
take the bike / car for a good long ride (to give an accurate average measurement),
fill the tank to the brim again,
make a note of the odometer reading and then
reset to zero again.
You then write the mileage on the till receipt (which then tells you how many litres / gallons you've needed to do the recorded mileage) because trust me, you wont remember the mileage by the time you get home - especially after you've had a
Eg on my last trip my odometer reading was 107 miles and the till receipt showed 10.71 Litres ie just under 10 miles a litre. To convert Litres to Gallons, just divide by 4.546 ie 10.71 Litres = 2.355 Gallons. Gives you a figure of 45 MPG.
Sounds a bit "anal" but a mechanic mate of mine suggested keeping regular MPG figures, as he reckoned that drastically reduced MPG figures may indicate a problem.


