[jonathan180iq]

If it's not running in RES, then there is a either blocked pick-up screen inside the tank or some other form or obstruction in the petcock.

If the vacuum pulls the fuel through in RUN, then it should also do so in RES.

Check and see how well the bike runs if you set the petcock to PRI.

My first gut reaction when reading this was a float problem. The PO probably did some carb work because there was some sort of starting or running issue that they "fixed" by messing with the carb, as you have seen. One of the hardest parts about a new previously owned vehicle is trying to figure out what the hell someone was thinking.

If the smoke out of the front of the bike was black, then you've got some carbon build up that you need to burn off, probably caused by the all of the rich running that you said it was doing before. There is a crush copper ring gasket on both headers that you can replace to help seal the area a bit. It is kind of common for a bit of seepage here because of the simplistic type seal - but billowing black smoke shouldn't be happening, obviously.

Check your valve clearance when you can and once you get it idling and warm, then adjust your idle speed.