Since new, I made an effort not to strain the engine, either by letting it labour in too high a gear, or by over- revving it in any gear. For approximately 500 kilometers, I took care not to exceed 100 km/hour in 6th gear.
This paid off, and the engine never over-heated or used any oil, and now it goes 120 to 130 km/hour easily.
I drive 90 kilometers a day, 5 days per week, of which 30 kilometers is high-way driving where my speed averages 110 - 120 km/hour, and I keep ahead of many vehicles (speed limit is 120 km/hour).
I live in South Africa (Paarl), and commute to Cape Town and back every day, as said, 5 days per week, and I find the fuel consumption excellent (33 kilometers per liter, doing 110 - 120 km/hour). If driven slower, the fuel consumption will be much better, of course.
I fitted a small windscreen, and this really helps a lot with the "wind factor", as by driving above 90 km/hour, the wind really is a factor to consider. The bike really "drives on rails" in the known Cape South Easter, and keeps its speed even in these terrible conditions. I'm doing a lot of driving in rain too and the bike never "died on me".
I "look after" my vehicles and strictly adhere to the manufacturer's service intervals etc., and this really pays off.