One ignition coil keeps burning out

[dumbkid]

Hi. I've been lurking for quite some time and finally needed to post something. I've been working on a 1974 cb450 that I'm bringing back from the dead. It was last registered in 1983 and has only 2000 miles on the odometer. It was found in Perris, CA missing quite a few bits and pieces but the engine turned over and had good compression. I picked it up about a year ago for a measly $300 and have just been taking my time working on it. Engine was taken apart, has been painted and remounted into the frame and I have just finished wiring her back up.

I kicked her over and was able to get her to run for about 1 minute till she puttered out. SWEEET! Back to life after 20 years. Did this a few times and checked the pipes for heat. Only my right pipe was hot. Left one was cold. Then I noticed that my right side coil was really hot and started to bubble. I just have some no name universal ignition coils that I picked up from Dime City.

I ended up ordering one more to replace the bubbled one and installed it. Same problem happened again and I don't know what the issue is for both issues, 1 - the overheating ignition coil and 2 - the lack of heat on the left pipe = no ignition.

Things I've tried:

- Set the ignition timing and adjust the gaps (I did notice that one of the points were sparking a lot stronger than the other)
- Check for spark on both plugs. Yes, they both have spark
- Grounded the engine by sanding a couple areas where the engine mounts to the frame (just in case the engine needs to be grounded)
- Check my wiring around the area where the ignition coil is (condenser is new)

I did have one problem when I reassembled the engine where I didn't set the exhaust cam in the correct spot when installing the cam chain because I mistook a seam for the alignment mark. But I think I fixed that....I think.

Any help would be appreciated. Here is a picture of how she sits right now in my messy garage.

 

[teazer]

It's a little hard to diagnose by long distance, but that sounds like a dead short in teh wiring. maybe one set of points is shorted out or the points are miswired. You'll have to follow the wiring through to see.

 

[Sonreir]

+1 to what teazer said. When coils generally burn out it's because they're left on for too long without discharging. If your points are shorting out then the coil is never firing and so it will burn out after a time.

Take the plug out of the offending side and leave it attached to the plug wire. Touch the plug to something metal on the bike (the crank case is a popular spot) and try to start the bike. You should see a fat blue or white spark. If there's no spark then your coil isn't discharging and you'll need to trace it through to find out why.