I contacted the supplier and they sent me a new CDI box
I installed that and it has the rubber cap on the top which the last one didn't have. so it fits a little snugger. also you were saying that the plug should have a cap and not just the threads? mine has only the threads. Maybe the spark is not starveling all the way through
here are some pictures of my setup.
I will try the new oil mixture too 24:1
I am only 14 so this kind of stuff is a bit tricky