I get over 50 mpg 95% of the time, average is 52 on a 2001, Stage 1 Ivan's with 24K on't clock. I'm happy with that and keep up with most of the lads.
One year on tour with the boys this dropped to an average of 42mpg but that was fully laden and uncomfortably swift.
So, when touring Scotland this year and finding the Mallaig garage had closed just 10 minutes before we got there, I managed 220 miles out of the tank before refilling at Fort William. I had 4 litres left so could have got up to a range approaching 260-ish at 58mpg. However the 40 miles to Fort Bill at 60 mph is no way to treat the A830.
My buddies on Viffers rolled into the garage with 1 litre remaining! But the BMW 650 rider was disappointed with only 72 mpg. Different strokes!