2017 R NineT Scrambler fuel mileage and reserve question

I had to bring my son fuel, he was out on the side of the freeway. 140 miles on tank 26 since the reserve came on.
Now granted he is 22 and gets way worse mileage in any vehicle than I do (I wonder why )
I have gotten 160 without light coming on. Is the reserve only 26 miles ?
Is the light consistent?
It’s a little frustrating to have no fuel gauge (same issue with my ‘01 R1100R, no fuel gauge and the reserve light does not come on. I cleaned every thing in tank and no change.

I don't own a 9T (yet), but there are a lot of factors that come into play that will affect the reserve - tire pressure, wind speed/direction, windshield size, panniers, etc. Was the tank all the way full when filled last?

Looks like the scrambler has a 4.7 gal tank, including approx. 0.8 gal reserve and rated to get 44mpg at 55 mph. Looks like the newer models now have a 4.8gal tank? All of these are approximate from BMW. That calculates out to 30ish mpg for the 140 miles, which is probably doable if you're riding 75mph and enjoying the throttle. I'd be curious to know your son's mpg on his previous tanks.

Well the scrambler has no fairing at all. My “kid” is 6’ 240 lbs. I can guarantee he was doing well over 80.
I have trouble keeping up.
He started getting 35-37 but usually I would have put some of those miles on there and I get 40+
I get 40-44 on my R1100R (also naked )

Here in SoCal we have lots of hills and I am sure he does them full speed.

I am sure this is a learning experience. Not that he will slow down. He will fill up sooner