That's quite a bit of oil. I doubt your engine is burned up. You might try backing that down to 4 or 4 1/2 oz to a gallon.
If you have spark, and gas is making it down the line to the carb, you might want to just take the carb off and clean the jet, the float needle and the seat, the passage where the gas comes into the float bowl. Any bit of grit in there can hold the needle valve open and the engine will flood.
If it was to stick open while it's running it can really throw some fire.
I had a Yamaha Roadstar that got a tank full of filthy gas and did it. A 2 foot flame just about took my eyebrows off.
Before putting the carb back on try tightening the pivot screw on the choke plate. They get loose and the choke turns itself on, causing trouble.
I hope you find the trouble, that's about all I have.
There are guys here that will have more ideas.