My 250X is runnin a little lean right now, it dies when I pull the hotstart and pops and sputers a little, and the plug is a litle whitish. I have a 162 main right now, if I remember right, and the needle is in the 3rd position. I think all I have to do is move it to the fourth position and it will cure it. So, can I do this just by taking the 17mm nut off the bottom, or do I need to take the whole thing out again? Right now I have the nut off, and I think the main jet, its the round gold one.