The emulsion tube is the needle jet here in UK. It's good you cleaned it out but what you said is a little confusing...it's not the pilot jet.
Heres a mucky needle jet
Pilot jet location ( somehow I feel you know this already)
Another thing to consider is
on some of the mikunis there is a small hole, the air jet. and worth checking its not blocked, this is an air intake that is regulated by the mixture screw
Last but not least there is a tiny passageway which goes between the carb venturi at the bottom just behind the throttle valve...and the cavity around the needle jet (I think)