FAQ rejetting and Needles

Needles are not available for every year, make and model. Sometimes the carburetor that needs a needle does not have a conversion chart to go from OEM needles to optional needles (that is because the carburetor manufacturer has made a proprietary needle for the OEM) and it is confusing to determine what needle to use. The choices are Mikuni and Keihin carburetor needles.

If the carb is Keihin, they make nice charts and we choose a needle off the chart. The best place to start is a needle that is in the middle of the chart. Install that needle and test. After testing it will be easier to choose the next needle because it will be known if a richer or leaner needle is needed.

If the carb is Mikuni, it is a little more difficult. As an example lets say a richer needle is needed. To get a richer needle we need a needle with a smaller diameter. If we want a leaner needle we need a needle with a larger diameter.

Go here to look for needles.