So, I removed the stock screw(had to drop the float bowl, couldn't coax stock needle out), and now the new one is not threading in easily. I figured I better check here before I try to just jam it in..... The shaft below the threads of the new adj. needle is bigger than the stock needle. Is this normal? The bike is an 02 ktm 400sx. Pkg(system tech racing, 70-02)says ktm 250-530, but not year. Pretty sure it's the stock fcr carb. Any ideas?