Long story short since I did this once and it kicked me out for some reason. I've got a 1983 CB1100F with an MSD MC1 on it. It's been great for 40,000ish miles.

Recently the bike has died on me while running 80+ on the freeway. I hit the start button and nothing. There's enough battery to run the lights, but not the starter. I get the thing home and check the battery and its at 10.9V. Charge it up, its 13.6, hit the button, bike fires and runs great again, for 65 miles. It's 66 miles round trip to work. Check the voltage again. 10.8V. Charge the battery again, starts, runs fine, but dies in 30 miles, not quite to work. Buy a new battery, fire it up, 13.6 becomes 14.75, with the bike running, comes back down to 14.25 the way it should. Its all good. 65 miles later, dead on the road, new battery is at 10.8.

I checked the entire charging system. It's perfect. What I did find was a 1.9 Ohm draw between the positive cable and the ground. The only thing that is being checked right there with the key off is the positive and negative cables of the MSD. I assume there is not supposed to be a draw there with the key off. Can I send this in to be fixed? If I could by another 4210, Id do it in a heart beat. One other thing, Ive been running .5 Ohm coils off a Cavalier with the 4210 for those 40,000 miles with out a problem.