Keihin Pilot Jet kit 139QMB Scooter Parts N-MP-07090 PILOT JET KIT ( Same as Stage 6 and Koso but in MRP brand ) Keihin Pilot Jet kit is essential to tune your carburetor for different elevations and when you increase displacement with a big bore kit. Included sizes. 35 38 40 42 45 48 50 52 55 58 PILOT JET KIT ( JET SIZES FROM # 35 TO # 58 ) SLOW JET FOR CHINESE SCOOTERS FOUND IN 100cc - 150cc * Fits RS Series carbs * Sold as pack of 10 VM28/486 MSRP $30