Very Strange Engine Trouble

I agree with Fabian, and not because of financial interests but because it's true. The stock CDI craps out easily and has too advanced timing, especially if you increase the compression and put a better carb on, and especially if you port the engine for higher speed.
Unfortunately the stator coil craps out easily too and you should always have a spare on hand. But some people replace them without realizing the problem was bad metal to metal contact at the coil mounting screws which serve as part of the ground path.
 
I'm waiting until the end of the month to buy a better CDI, I was leaning towards this
http://www.sickbikeparts.com/catalog/product_info.php?cPath=22&products_id=184
but two people have mentioned the "Jaguar" CDI, is there a noticeable difference? The key used in the first one kind of drew me to it. Any other recommendations for things like mufflers and carburetors?

this is the coil I upgraded to when my stock CDI crapped out in less than 200miles.
the new coil has 500+ on it and counting...
I don't joy ride either. when I fired it up, its going to run no less than 26miles round trip for the day. up to 90miles for the day depending on where I have to go.
 
The Jaguar CDI has adjustable ignition curves, which is an important feature, especially if you are going to use a higher compression cylinder head and/or different types of fuel.

The ignition key is relatively pointless because it's another component in the electrical system that's waiting to fail, and should you lose your key, you won't be going anywhere, and as we all know you "WILL" (at some point) lose your key; when you desperately need to use your bike.
Secondly, the lightning CDI doesn't have adjustable ignition curves, which doesn't make it much different from the standard CDI.

You are better off spending money on a decent bike lock if you are so concerned about your bike being stolen.

There is no significant difference in performance between aftermarket CDI's and the standard CDI, going from my experience, however the Jaguar CDI (from my experience) dramatically improves engine life, compared to the standard CDI.

If you want a noticeably smoother engine (at the expense of slightly lower engine power) you can adjust the Jaguar Ignition curve to the lowest setting.
 
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click on my signature link to learn more about the Jaguar CDI (now called the Performance CDI) and other options for upgrading these engines
 
Well, turns out my coil was broken and the new one works. I checked it with a multimeter and got zapped pretty bad when I held the spark plug and turned the tire. I put everything back together and the engine still won't start. I did notice that if I hold the spark plug by the wire I won't get a spark, but if I hold onto it or hold it on the frame of my bike a get a very consistent and visible spark. So now I'm thinking something went wrong in the wiring, or possibly in the kill switch. What do y'all think?

I have my wires set up like they were before - blue to blue, black to black, the yellow wire from the kill switch connected to the blue wire, and the black wire from the kill switch connected to a screw on my bike frame.
 
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I've got blue to blue and black to black from loop to coil. My yellow from the kill switch goes to the front motor mount. Green from the switch to blue between the loop and coil.
Doesn't sound as though it should make a difference with the kill switch being a momentary connection.
You may be right on the bad switch idea...
 
I reread your post... you mention a dfference when holding it by the wire.

Is the connector at the top of the boot fully engaging the top of the plug? Has it stretched or worn from instalation and removal? Is the wire broken inside the insulation?
It may arcing some where before it gets to the plug...
 
when you say your coil was broken you don't say if it was the high voltage coil or the stator coil.
not allowing the spark a return path via the frame of course would prevent its occurrence and does not indicate anything is wrong
 
Disconnect ( cut ) the yellow and green wires from the kill switch and see if it starts.
 
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