One thing that does help is to ditch the cheapie batteries you have to fill with acid yourself, and get a sealed battery. It helps, but the charging system is still marginal. Honestly, if I had just bought that control pod that lets me turn off the headlight, I don't think the re-wiring or going with would have been necessary. Just that and the LED bulbs I think will be enough. I mean, you have 1157 bulbs in the turn signals for front running lights, and 1156 bulbs in the rear signals. Plus two 1157 bulbs in the taillight housing. That's 8.3W for each front running light and taillight, plus 23W for each brake light and turn signal. With two taillight bulbs, that's 33 watts of power with the brake lights off. 62.6 watts with the brake lights on. Plus an intermittent extra 46 watts when the turn signals are on. And then 55 watts for the low beam. Going to LED bulbs does really help, and turning off your headlight in stop and go traffic does too. There's also now the option of LED headlight bulbs, which consume a lot less wattage and are still hella bright. They're pricey though.
Ohh, plus each bulb in your speedometer and tach housing is 3.4 watts. Two in each bucket, plus one for each idiot light. So going all LED will definitely help you a lot. It did help me back in the day.... back then though LED bulbs were a lot dimmer than they are now. You can really get some great brightness for not a lot of money these days.
I mean, I had mine working well. If I let it idle too long voltage would still drop, but it was honestly SO much better than stock. SO. MUCH. BETTER. The only times I really had trouble was when I was in stop-and-go traffic for 30-45 minutes.
Charles.