Filling the fuel tank up all the way, on the sidestand..
Dividing the Trip Odometer mileage by the number of gallons pumped..
So far, the trip odometer is pretty accurate compare to the posted miles between cities.
My overall average on a weekend trip to Dawson City, YT was just a hair over 58 miles per gallon... and I ride FAST.
Warm enough to RAIN is warm enough to RIDE.