Been saying air/fuel from the start. Even when I mentioned jets I said that wasn't the problem, same with the overheating not causing empty bowls and so on. Thats why I was asking about the filter and now that I know you have been running it and you cleaned it that doesn't seem to be the problem either. So it's seems its to the vent or sticky float/float needle or a partial blockage in the gas line after the clear line. Might run a little gas line anti-freeze through it while the bowl drain is open to eliminate some ice as the possible blockage (don't know how cold it is where your bike is).

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