[Badpuppy]

One 50 CP bulb is about 36 watts, or 6A at 6V, and increases with higher voltage. Total head/tail lights + coil current draw will run 15-16A at 7V with a well-charged battery. The cutout contacts close at about battery voltage, so your meter shows the battery discharging 8A, the rest being provided by the generator.

You could adjust the 3rd brush for more current, less discharge of the battery, but I wouldn't want to push the generator over 12A continuous. Depends on how much driving you expect to do with headlights on. If not much, you're probably OK as is. That brush adjustment is more an art than a science.