Won't turn over with key
 

My ASW GY6 won't turn over when I turn the key. It does turn over if I jump the solenoid. Could it be a bad CDI? Not for sure why its not turning over. I recently purchased it and after a minor rebuild I'm frustrated that I can't get it to start without jumping the solenoid.

Check the ground connection!!!!!

So I tried the ground and it was fine. It turns out that when I changed the starter and solenoid , the wire that leads to the solenoid from the (voltage regulator)? had an end that matched so I plugged it together. But it was the wrong plug end. There was another plug end that did not match that I had to splice together and when I plugged these together walla.
So the way I figured it out was that I kept the original and compared the two. The plug ends are different.

Glad you figured it out