I’ve been trying to set the points on my new to me ‘79 1000SP with factory wiring and coils. The right side points adjusted fine, but the left side were showing continuity to ground even when open. They would only show no continuity when both the left and right points were open. After chasing down all of the wiring I found that the right points when closed were grounding through the trigger wire to the right coil, which was then grounding back to the left points through the left trigger wire. I guessing this was through the power jumper wire between the coils.
I’m guessing also that there shouldn’t be continuity in the coils between the trigger spade and the power spade. I wired a diode into the right trigger wire near the coil to allow the trigger voltage from the right points to the right coil, but not allow continuity the other way. Now the points test fine with the ohm meter.
Is this just treating the symptom? Is it possible that insulation between the coil spades is defective? Wouldn’t this situation only be possible if both coils permit continuity between the spades? I’ve checked all other possible ground paths and found none.
I could just buy a Dyna III but since I’m probably going to flip the bike I’d like to keep the expenses down a little. Also I’m determined to get better with points. Usually I install EI and punt on learning this.
Thanks everyone. Here’s the wiring diagram - credit to Greg Bender.