Alright thanks guys, so that clinches it- my mileage sucks, at 50-60 miles before needing to hit the reserve. I didn't completely fill it though, trying to leave a little room at the top, but it was pretty close to full. I will get better at consistency there, and I finally figured out the trip odometer on the speedo thing so can do a better job of tracking that as well.
What was interesting was it was all at once- no sputtering, no hesitation, just went from running to off. Is that how your bike runs out of gas?
82 fj40, 99 uzj100, 06 gx470
05 525EXC, 01 XT225, 09 TTR125, 07 TTR90, 07 CRF50