Ok jgar. I took the carb off. Pulled plug. Sprayed starter fluid in and replaced plug. And no go!!!! Now I don't have spark. Wtf is happening? It has new CDI. New regulator. New everything. Fuse is not blown because its turning over. I think it's the spark plug coil. When I received the 400ex. It had a 300ex ignition coil. And it's rigged wiring

 

Wow dude, that thing is fighting you the whole way.
Does the plug look good? At this time replacing the coil would make scene. You have gone over the entire electrical system and everything is tight and right?
Why would you take the carb off to try to start it starter fluid in the cylinder?

 

I took the carb off because it sounded like it was constricting the air flow even with the choke open and throttle open. I just wanted to here if it would crank up. But it's not now. No spark. And now I have to put more money into a new harness and ignition coil. Cuz the guy that had it before me cut the stock coil wires off and rigged a 300ex coil on. I just need someone that can fix this pro bono lol

 

When you do get it running. Its going to be a brand new machine with all of the work you have done.

 

Damn with all the work you put in it it's hard to say but if it's still not running after the new coil check the timeing agin just to be sure with it puffing whit smoke like that sounds like timing to me

 

Ok guys I got some time yesterday to fool around with the 400ex. It wasn't the coil after all. The CDI was going out. I put my crf100f box on it and its firing now. Took the carb intake boot off. Sprayed gas in it and it fired up for a second the. Heard the timing chain rattling around and sound like its slipping. And my tensioner is tight. Can't I take a link out of the chain and put it back on but loosen the tensioner up?