I never had a bike with a fuel gauge. Most bikes before fuel injection have 3 positions on the petcock. On,off,reserve. You run the bike with it on the on position and when that runs out you switch to reserve and find a gas station. Many people learn how far they can go on the on position and know to start looking before reserve.

I learned all I need to know about life by killing smart people and eating their brains.
Eat right ,Exercise ,Stay fit, Die Anyway!