Our company is involved in a school "mini-chopper" program that has teams of students build bikes to learn mechanical skills.  The engine purchased was a Lifan 250 using a Mukuni DBS26 carb.  We have not been able to get the bike to run properly with it either running wide open or at a very poor idle if you close off the throat of the carb.

Does anyone have a manual that shows correct installation of the carb, fuel and vacuum lines.  It seems something is missing in the install literature that came with this kit.