I tried to measure my Versys precise fuel consumption and tried for the lowest consumption. Here are results.
On last trip it was 59.7 MPG (U.S) or 3.94L / 100km. Error I think is less than 4%. Worst case: 57.4MPG / 4.1L/100km due to inaccurate odometer and refuel.
*new 16/43 tooth sprockets and chain;
*new Motul oil with filter;
*new NGK spark plugs;
*speed below 60 m/h (80-95km/h) on flat country road (5% city driving);
*rpm below 4000, gentle driving without odd breaking;
*trip odometer correction (had to multiply with 1.13, counts less, than actual) ;
*trip was 179km (112miles), + - 1km error checked with google maps, bing maps and road kilometer signs;
*fueled to the top, and refueled 7,09 liters in the same station after trip to the same top;
*weight with me, topcase and bag on shoulders ~ 120kg, my height is 1.92meters, original windshield and it wasn't windy;
*tyre pressure checked (2,5/ 2,4 atm);
*fuel type: 95E
*ovarall odometer milage: 24 000km (15 000 miles);
*air temp: 16~20 degrees Celsius (60-68F).
If you want to know other owners MPG check www.spritmonitor.de