Do you have access to a multimeter?
I need you to run a couple of tests. The first would be to check your battery voltage. Connect the meter to the battery and check the voltage. Turn on the key and check the voltage. Start and run the motor and rev up the engine. What is the top voltage?
You should have 12.6, 12.3 and 14.5 volts as your readings. Let me know what you get.
Usually the only cause of repeated CDI failures is voltage spikes or a problem with the ground system. The charging system test will help me to know what's going on.
I will look for an aftermarket CDI for you. Does it run now??? If not, it will be nearly impossible to test the charging system, although the battery may show an abnormal state of charge.
I'm not showing any aftermarket CDI's for that, but there are stators and regulators. I would try and borrow a meter or buy a cheap one. Many auto parts stores will rent them cheap or you can get one at Wal-mart /Sears/ etc for $20. Without running any tests I wouldn't put parts in it.
OK, it's going to be very difficult to test the charging system with the machine not running. The regulator and stator tests are much more involved. I am uploading the electrical manual for you. It cover the ignition and charging systems, so you will be able to test every part.
Have you tried plugging in one of your bad CDI boxes in another machine to see if it will run? It's possible your CDI is ok but your stator coil or trigger is weak.
Click on that link and download the manual to your computer.
Without the machine running I can't give you any shortcuts. You may have to run all of the tests.
That's not good. There must be a short or problem in the wiring to cause that. I'm going to go over the wiring diagram and consult with another tech. I'll hopefully have some ideas on what to test next.
I'm having problems with my wiring diagram. It's missing some of the information I need. I have contacted another tech to assist me. I apologize for the delay.
That may be the issue, but it could also be something as simple as the ignition switch. Somehow voltage is coming into the CDI where it shouldn't or in higher amounts then normal.