Hi my bike also smoked a lot when i was runing premix.
i dont think you could get leaded gas at the pumps anymore.
but what you are saying is one side more then the other, i had that too before my oil pump broke, might be a sign. check the oil lines from the pump to the carb, maybe one is not clean...
can be a lot of things realy, more people will be here shortly having different views. so just hang on. best of luck mate, i know its a problem.
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