how's it going? i'm just a newbie, but i have encountered a similar problem and have been able to fix it. the problem with mine was that it was flooding out major big time, it was blowing fuel right out the tail pipe of the cylinder which was not working. was able to source it to the carburetors... where i found that the main jet had backed itself out, and was just sitting in the float bowl!
once it was tightened up again, problem solved. i made sure to check the other one at the same time. a good way to check if the problem is that it's flooding is to turn the fuel off and run it, and if the second cylinder starts firing just before it runs out of fuel, it's probably the same problem as i had or something similar.
hope this helps
have a good one
josh
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why do it in 4 strokes when you can get it done in 2