The needle is inside the slide in the carb. It is a tapered rod that moves up and down with the slide and actually goes inside the main jet. It determines what your air/fuel mix is in the mid range. Screw the top off the carb and lift the slide out. Then if you compress the return spring you can remove the keeper and take out the needle. It has grooves on the top and a tiny slip ring that fits in them. The middle groove is a neutral setting, higher (toward the top of the needle) lets it go further down into the jet and leans out your mid range while lower holds it up out of the jet and makes the mid range richer. At wide open, it is pretty much out of the jet and lets it run. Be careful, that slip ring is tiny and easy to loose. Those parts will all be slippery because of the gas/oil mix that goes through the carb. If it bogs a little in mid range, then comes on when it gets some rpms, you probably need to lower the needle (raise the clip). If you are getting some detonation in mid range, you should raise it (lower the clip). This is all done when you are satisfied that you have the correct main jet. It helps throttle response tremendously and makes riding easier and more fun. Good luck! [img]i/expressions/face-icon-small-smile.gif[/img]