I am not sure about the air filter but, I think mine was 28mm, not 38, I could be wrong on that. That jet is not the same as the one in the carb I had. Mine didn't have the head on it, the whole jet screwed up into the thread. Mine was a 2007 model and did not have an adjustable needle either, I don't know if your carb is the same as the one I had. Zombie's carb had an adjustable needle, which is the same as the manual. I don't know when, but at some point they seemed to change the carbs.