It is a Mikuni carb.
I go through about a litre 1 month.so about every 4-5 tanks of gas. There really is no cloud of smoke behind me when i am driving it only smokes on initial startup and if i sit there and let it idle for a while. I am not sure but i think the guy may still have all the emission controls and stuff that he took off. It is just a matter of getting a hold of him and finding out where evrything goes