I'm pulling what's left of my hair out. I have a 94 tour glide. The fuel gauge reads below empty. I have checked the sending unit and ground. If I straight wire 12v to the power side of the gauge it works. I have voltage coming to the gauge, however it is only 10.6v. I assume this is why it doesn't work. I have 12 at the switch with the switch off. When I turn it on, only 10.6. I tried another switch off of a working bike. Still the same. Can't find any bad wires

 

Many electrical problems are actually mechanical. You have proved the guage works, so it can only be a poor connector, broken/damaged wire, poor earth/ground, something infuriatingly simple! Have you got a buddy and a case of beer, so the two of you can check things over together? A second pair of eyes and brain can often work wonders! The beer is for celebrating later.....

 

The beer fixed it! I had 2 problems. My battery was starting the bike, but had a dead cell. Under the load of my headlight, it was drawing down to 10.6v. The other, my sending unit was coroded between the bracket and the part that screws to the tank (too much resistance) but it had slight continuity. Lots of beer, new battery and cleaned the sending unit = gauge works fine!

 

Brilliant, well done! Beer can work wonders when skilfully applied....