Carbide 150cc - Fix for poorly running engine

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I have owned the American Sportworks Carbide 150cc go kart for about eight years now. Since I bought it, I never felt that it ran as well as it should. It would often stall, and the idle was never all that stable. I didn’t experience any real issues, so I accepted that it was just the way the engine ran. At about year three the engine started running very poorly and I felt that carburetor was messed up, so I bought a new carburetor. A new carburetor was not much more than a rebuild kit and I couldn’t justify the time rebuilding the carburetor. I installed the new carburetor and the engine was back to running the way it had originally ran. Since then, I have replaced the carburetor every time the engine started running very poorly, which has been about every 2-1/2 years, and that always got the go cart back to its original running condition. I figured they were cheap Chinese carburetors and that was about their useful life. At the beginning of this year I replaced the carburetor again. This time though, it only took about a month or so for the engine to really start running bad. The engine would start up and an idle fine, but that was it. As soon as you tried to throttle up the engine, it would sputter and die every time. Now I had to dig into it some more, and I no longer believed it was the carburetor. First I contacted American Sportworks tech support and they were of no help with identifying my problem - I now call BS. I then found out there was a manual choke kit, so I figured this was a good place to star. I installed the manual choke and there was no improvement at all. I then tried a new regulator and that did not help. In the electrical box I noticed that there was a burnt yellow wire at a connector that has a yellow, green, and white wire. This connector was between the coil, regulator, and auto choke, After many hours of frustrating work and troubleshooting, I disconnected this connector while the engine was running expecting the engine to die, but instead the engine started purring like a kitten. I now figured some had to be wrong with the coil so I bought and installed a new one. With the new coil, keeping the old regulator, and now having the auto choke electrically disconnect, the engine ran as good as it ever did and maybe a little better. As quick test, I disconnected the green, white, and yellow wired connector and the engine started purring like a kitten again. I tried (not installed) the new regulator and got the same result. Looking at the schematic I determine that the yellow wire, which was the burned wire, goes from the coil, to the regulator, to the auto choke. Since the auto choke is now removed, I cut this wire and the engine now runs perfectly. Based on the schematic, removal of this wire should not impact battery charging.
BOTTOME LINE: REPLACE THE AUTO CHOKE WITH A MANUAL CHOKE AND CUT THE YELLOW WIRE AT THE CONNECTOR AND THIS GO KART WILL RUN LIKE A DREAM!!!
Looking back this appears to be an electrical problem all along and not a carburetor problem. I think that something is going on electrically with auto choke solenoid that has an effect on the coil, which then impacts the coil output for engine spark. So each time I replaced the carburetor assembly, which came with a new auto choke, the problem was temporarily fixed.