[eggsuckindog]

all I can say is isolate and eliminate - it works - try the different tank that isolates and eliminates the tank and fuel lines as well as the vent - save your money on another set of plugs that ain't it. Does sound like a fuel issue though but if you have drained the carb bowls and found no water anywhere I wouldn/t bother doing that again either - you eliminated that unless you found trash in them.

rebuilding carbs is nothing more than cleaning the bowls out - you did that - and new gaskets and a new needle and seat, I would pull the air box and make sure the carbs are not overflowing fuel which is eliminating the needles and seat. Do not run WOT without the air box on it - it will lean it out too much, just look for flooding carbs