Okay, I need some more help/advice on jetting my 00 426. I just changed my pilot jet from a 42 to a 40, I have an 01 needle in the 4th clip position, 162 main, 1-1/2 turns out on fuel screw, all other jetting stock. I first tried the 01 needle to solve my bog problem- almost but not quite. So I turned the BK mod in more, added the 40 pilot today- it got worse. Now its closer to when I had all stock jetting with 2-3/4 turns out on the fuel screw. It was only about 52 degrees today, which could have something to do with it. Could someone explain to me what circuit affects what throttle opening? This might help me better understand how the air and fuel are flowing through the carb and which jet to change to chase down the problem. I can open the throttle wide open from an idle, as long as I don't whack it wide open immediately. If it do it somewhat slowly, I have no bog at all. Any help/info would be appreciated. Thanks again to everyone for all the help in the past.