My 250XMax is listed as having a 12.5Lt (2.75Gal) tank...
The light comes on, and when i've filled her up i've usually added 9.5Lts, (2Gal)
Reserve from 'Light-On' is meant to be 2Lt - so about right...
And i've usually travelled apx 180 miles... so about 80 ~ 85 mpg...
So, 215 - 230 miles is a possible, but not always a practicle...

This is for Stop / Start commuting, so maybe a little better on-a-run...

I usually fill up on the way to work (in their time) rather than on the way home (in my time)
Or, when during a bout of rain etc like the other week, when its dry, to save the faff of arsing about in waterproofs / gloves etc, filling up, paying for petrol etc...

My CCM 650 Supermoto has a 9.5Lt tank - 2 lts of that is reserve (on twin taps - to get in to the 'wings' of the tank, both sides of the frame)
So, about 60 miles to reserve - 35~40 mpg... Thats about an hour to hour and a half of lanes... and ya arse and ears can do with a rest by then...

About 150 miles before running my Xciting (nearly) dry. I usually fill up after ca. 100 miles to be on the safe side.
I.e. yesterday after 89, 118 and 119 miles just when I detected a convenient petrol station.

100 miles are 2.5 - 3 hours full of turns and bends. I'm not on a 24 h race where I couldn't afford 5 mins for refuelling.
The "limited" range is no constraint at all, when I ride with motorcycle friends (which need a rest every hour).

gts is about 100 miles

the nexus 250 or 300 are probably the best easily 250 miles

My 2004 AN400 hits the red on the gauge at about 130 miles but there's close to a US gallon of fuel left. I'm comfortable up to 150 miles although I usually refuel at about that same 130 miles.

I just got 168 on my burgman k8

200-240 on the X9 for about £19.

Burgman 400 2010 mod 242 miles then it stopped, no spluttering no hiccups just silence.