Get MAXIMUM PERFORMANCE LONGER ENGINE LIFE EXHAUST POPPING? FEELS SLUGGISH? These are signs of a LEAN ENGINE, a Jet Kit will fix those issues. CBR400RR Kit Includes Main Jets Pilot Jets Needle Adjusters Nylon Needle Spacers Slide Spring Modification Drill Bits for Slide Hole Modification (optional) Idle Mixture Modification Intake Airbox Modification Exhaust Modification Tuning Tech Bike Specs Carb Schematic Carb Synchronizer Tool (how to build for $5) Step by step instructions with photos for ease of installation. Installation Support - If you need assistance we are there for you. BENEFITS MORE HORSE POWER Designed to gain a safe 8%-10% in HP with intake/exhaust, 3-4% on bone stock. MORE TORQUE By addressing 1/4 throttle, you will feel more power down low, meaning less shifting to a lower gear, and getting off the line. LONGER ENGINE LIFE 6SIGMA JET KIT is a performance upgrade that not only increases power, but allows the engine to run cooler and at optimum, which increases engine component life. INCREASED PERFORMANCE Designed to improve all RPM ranges of performance and a quicker throttle response, helps remove the bog. EVERY Kit Custom Engineered EVERY Time MADE IN USA