Best electrical setup recommendations

I need some help with a good reliable electrical setup. I'm running an ngkb6hs plug and Ngk 7mm wire but I keep having a problem burning up mag coils. I store the bike inside so i know it's not from water plus I have it sealed up. This is my 4th mag coil I've burned up in under 6 months. It starts as intermittent spark and than it goes wide open, every single coil does the same thing after about 200 miles. My motor is a pk 80 with a speed carb jetted with delrotto 65 main. Spark plugs are a nice chocolate color. I do experience problems at top speed where the motor will just shut off until I get to a slower speed and than take off again. I'm really getting tired of replacing coils every month so any help is much appreciated. Also cdo checks out as it should. My set up is mounted on a 29er and I can hit speeds around 47 mph flat ground on a good day which makes me think I'm putting too much load on these coils. Anyway any advice helps

I'd be checking that clearance is good between stator & rotor - a little tapping there could shake a coil to death. Also check that left main is tight as I've seen crank hop knock out a coil.

no mention of how the killswitch is wired, how often its used...

take the killswitch off and see if it lasts any longer. kill the engine by stalling it or giving it choke instead of using the killswitch.

Sorry guys. I never used the kill switch and I never hooked it up, I've been choking off since I built it. I'll double check the stator clearance but I'm almost certain it's not touching anywhere. As far as the left main everything's snug as a rug. Are there any options on these could that aren't from China? Like a good quality coil is what I think I need to do

never seen a problem like this in 6 years of doing these that wasn't caused by some type of vibration (maybe engine mounts loose?) or knocking between stator & rotor - never seen a replacement

are you sure the coils are going dead internally and not just losing ground somewhere?

Ditto what crassius said. Sounds like a ground problem, also, the cranks on these engines are sometimes not true. There's some cool videos on youtube from a guy who puts them in a lathe. Amazing how much they wobble. Since the air-gap on the magnet is tight, a little wobble will cause a wipeout in short order, not to mention what it's doing to the bearings and seals. I've only had 1 mag go bad in all my dealings with these engines, and that was due to water getting inside the case.