1st there's a gen light, then there isn't, then there is...

[Garnet]

It's a '72, so it has no fuses.

Fuses started midway through 72. Still cleaning the contacts inside the ignition switch should help. You might have to disassemble the switch as it is the upper contact the supplies power to the 58 terminal, not the exposed lower contact which is the main switch. I've never been inside one of those switches so I may be all washed up.

[Deleted User 62]

I think you may be right, Garnet. I'm looking at a disassembled switch right now, from another bucket torn down for painting. There doesn't look like any feasible way to clean it in place. Short of spraying some contact cleaner in there and wiggling it around, it has to come off. It's been hard to get the key in for as long as I've had it, so it's time to do it. I have the parts to convert it to fuses and eliminate some bodged wiring too.

[hools100RS]

Tim, l was having the same problem as you describe albeit after a prolonged hassle with light just glowing a little at times..... going out completely at others ,etc, etc. The earth wires to the diode board were showing signs of overheating as well....... I just bit the bullet and changed the diode board and problem solved. My rotor and regulator tested fine. Hools.

[Deleted User 72]

After tilting at my GS's charging system for toooo long, I heartily reccommend adding Rob Frankham's heavy gauge ground wire from the diode board to frame to battery. My charging system worked not at all until I added the ground wire. I know this is not the entirety of your problem but its valuable just the same.

I added a simple rocker switch in the seat lock hole which parallels the ignition switch on my /5. I had problems with the ignition cutting out intermittently while riding.

Before I forget, big ground wire!

[Kurt in S.A.]

If the rotor goes open, the light cannot come on as that is it's path to ground.

The light goes out when the voltage on one side (from the alternator) and the other side (the battery) are essentially the same. If the rotor goes open, then there's no voltage from the alternator, an imbalance (or differential voltage) across the bulb, and the result is a glowing bulb. That's the way I understand it.

Kurt in S.A.

[Deleted User 62]

It was the diode board. In the process of attempting to troubleshoot the ignition switch, I ended up with an alternator light that would not turn off, even with the ignition switch pulled and the brushes making no contact (?)! With the ignition switch in, the starter wouldn't turn. I had put in a new starter switch yesterday, before this trouble started, so I knew it wasn't that. Swapped starter relay and regulator, the ones on the bike were crusty originals, but still that light was on. Finally put in a new diode board, and then everything worked, except the oil light... fixed that in 5 minutes too. The ignition switch is still iffy, but I'm going for a ride!

[dwerbil]

Good deal, Tim!

[Garnet]

"The ignition switch is still iffy, but I'm going for a ride!"

Go ahead, take the easy way out.

[Zombie Master]

Oh Wanita, I call your name.

[Deleted User 62]

Not to worry Garnet, even though I took the "easy way out", by replacing everything else I still want to do something about that switch, it's currently hanging by a thread. On the plus side, the bike turns off when I center it... soooo much easier! I had my '73 next to me when I was perusing the headlight innards, and noticed there are marked differences between them. While the main harness and switches were the same, the way the instrument lights etc were wired was interesting. The '72 had a yellow with red stripe wire coming off the switch board powering the instrument lighting that wasn't in the '73. I wonder why they changed it.