You smell it in exhaust too? You may have a float bowl problem. This can contribute to a rich mix in one or both of the cylinders. Fuel is probably blowing by the piston rings. I also believe I heard that the petcocks are vacuum operated on these bikes. If they stick open fuel flood are a problem. Then again good floats should stop the fuel right?
Pull the carbs, set em on bench, hook up a gas line and feed gas into them. if they dont stop fuel flow then they have to be taken apart and cleaned/ adjusted. I dont know of a way to check floats while on the bike. maybe a carb head can chime in on this.
Someone around here might have a download link to that manual and maybe the service manual as well.
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