There is something inexplicably pleasing about the CB1100

[tinboatcapt_imp]

If you under fill a previous tank, then over fill the next, the calculations will show a lower than actual MPG number. You have filled the tank with more fuel than was required to go the distance on the smaller amount of fuel. Odds on a lower fill on the next tank will show fantastic mileage. I keep a running five tank average which is more consistent, and a better indication of things changing with the bike.
Jim