Dynojet Recalibration Jet Kit For Harley Twin Cam Features: This kit from Dynojet is the perfect solution for eliminating flat spots in the acceleration It permits easy tuning of the carb on stock motors as well as motors equipped with performance cams and exhausts Comes with a detailed instruction book that leads you step-by-step through the carb tuning and modification Included are a selection of main jets, a needle jet, an adjustable needle with spacers and circlips, a spring and drill bits