I have got as high as 49 mpg (imperial gallon) but that is on the highway between Revelstoke and Kamloops which has a drop in elevation (downhill) and a heavily enforced 90 km/h speed limit. On my commute of 20 minutes on rural Alberta highway running at 120 km/h, no warm up, I get 35 - 40 mpg ( imperial gallon), weather dependant (can't get any more than 35 mpg at -30 degrees C).