I constantly get about 70 mpg with local use even with a very high mileage of 32,750 and 80+ on runs. It also improved when I changed the belt as the rpms reduced by 1000.
I agree that the fuel gauge is not accurate. I can run it well into the red bottom zone and still put less than 11 litres in, so still has about 2-2½ litres left (assuming the 13½ litres capacity is correct). See my Fuelly figures below.

Had my SR Max for just under 2 months now, and I've pretty much sussed out that I'm getting 20 miles to the litre, 15 litre tank makes that around the 300 mile mark. I'm comfortably getting 240 miles (6 working day journeys) before the reserve fuel light flickers on and off, theres around 3 litres still left in. Economically far better than the carbed XEvo it replaced.

Getting about 50mpg on the Max... thirsty little minx she is

I get about 130-140 on my Burg with a large Givi screen and side wind deflectors. On European trips when it is fully laden and doing between 90-100mph, I get just over 100 miles before the gauge is flashing like mad.

My 400 L2 does around 67 to the gallon. Admittedly it is ridden pretty hard at times, but even going a lot steadier it doesn't seem to improve much. Changed the standard air filter for a K&N at just over 2000 miles as the original was black

I usually get a minimum of 200 miles to a tank and thats with very mixed riding which is around 49 mpg .I have however had around 55 mpg when being a bit more gentle with the throttle .

115 is as far as I dare go, did manage 125 once, but I was down to 40 mph for the last 20 miles or so...

Check my fuelly below