Engine not starting, ran it with an exhaust leak

[Chainlube]

Found this with the magneto. When I try to install it so that the cap is even on both sides it just goes back to where it was because of the screw holes. Should I drill the holes in the magneto bigger? Or how should I fix this?

I assume it ran fine before like this because the screw holes don't seem to allow any kind of movement.

But not an expert.

Get a round file and file the side where the coil has to move. A few swipes is all it will take.

 

[robe]

Found this with the magneto. When I try to install it so that the cap is even on both sides it just goes back to where it was because of the screw holes. Should I drill the holes in the magneto bigger? Or how should I fix this?

I assume it ran fine before like this because the screw holes don't seem to allow any kind of movement.

But not an expert.

I will try to flood it and start with full throttle.

How can I check the spark timing? Maybe that's the issue. I took the magneto off a couple of times when the engine was sitting.

"I took the magneto off a couple of times when the engine was sitting."

That could be the issue there. It was working before you did whatever you did. One thing I have to say is the gap between the stator arms and the magnet seem to be pretty big. Usually the gap is a couple business card thicknesses at most. Maybe try and reduce the gap to something more reasonable.
My initial comment was the magnet's key may have fallen out because the bolt came loose or something like that and wacked the timing off.

 

[BikerRay]

Well, I fixed the magneto and bike is still not working.

Even tried the old plug, tried full throttling it and flooding.

Does not start nor fire.

It has compression but maybe it's not enough? Could the piston rings or something similar be broken?

And what should be my next steps?

 

[BikerRay]

Well, I ordered a new engine since there were no more tips.

I would still like to know what the issue could have been.

Maybe it died because it was a fairly new engine, and perhaps I full-throttled it a bit too much. Could this have broken something?

I plan to take the engine apart.

 

[BikerRay]

Could the CDI have failed, even though I see a visual spark and the RPM meter registers a spark?

 

[Mr. Herron]

Could the CDI have failed, even though I see a visual spark and the RPM meter registers a spark?

Could be your kill switch,try taking it off the start it. Or a different carb.

 

[Johnny_]

Could the CDI have failed, even though I see a visual spark and the RPM meter registers a spark?

Could have been the CDI, it could be sparking but not good enough. I don't think full throttling it had anything to do with it. Yeah it could break something, but you would see it. It's not like engines just break but everything is fine on inspection. If it's broken bad enough to not run, there will be SOMETHING that is wrong on inspection.
Also like Sherron said could have been your carb.

 

[kiwigasbikes]

Here's an idea, get yourself a sheet of 150 or 120 grit sandpaper, and a sheet of glass. Tape the corners of the sandpaper down on the glass, flip your cylinder over and sand off those lines on top. Then do the same thing with the head. Wash them both in warm water and dish soap, then reassemble with a new gasket.

Now for the exhaust side, get a O2 sensor gasket, ask politely someone will let you know which one, and put your muffler back on and double nut the studs.

I saw a video just yesterday - it was the EGR valve gasket on an O5 Toyota Highlander Diesel. its a metal composite gasket and very strong

 

[DAMIEN1307]

I saw a video just yesterday - it was the EGR valve gasket on an O5 Toyota Highlander Diesel. its a metal composite gasket and very strong

Yep...lol...I don't know about an EGR valve gasket but I DO know about the Toyota Highlander O2 sensor gasket that is pretty much an exact fit for run of the mill China Girl motors with the 40mm stud to stud exhaust port.

And I gave all the information about it to the OP already on page two including a URL ink as to where get them at...lol...lol.

Engine not starting, ran it with an exhaust leak

Now for the exhaust side, get a O2 sensor gasket, ask politely someone will let you know which one, and put your muffler back on and double nut the studs. This gasket is only for common China Girl motors exhaust like the 66/80cc and the 77/100cc motors with the 40mm stud to stud measurement...

motoredbikes.com

I'm still waiting for the OP to acknowledge this recommendation for a replacement gasket but he seems to be chasing down many other problems first it seems...lol.