I'm sure that longer distance riding +160kmh (+100mph) will increase the fuel consumption
My K6 drank closer to 1 liter per 10km on autobahn with 2 persons, lots of luggage and seldom under 160kmh. Mostly 170-180kmh. Stop for refuel every hour.
Reducing to 120-140kmh better to avoid too frequent stops. Riding slower took us longer quicker.
I have not verified consumption on my K2 with K7 pistons that kicked up the compression and action to a healthier level.
Stock compression to handle crappy fuel in strange countries?