10 HOURS ON THIS SYSTEM FOR Honda Crf450r 2013-14 year models Introducing the all-new RS-9 Dual. The CRF's new dual-muffler configuration gave us the opportunity to create an entirely new muffler built specifically for the dual-muffler CRFs. We worked with Top AMA Pro Riders to achieve maximum performance and mass centralization, and to optimize rider usability. We achieved all this while maintaining AMA Regulation sound levels. The RS-9's uniquely sculpted Carbon Fiber end-caps feature a Tunable Insert System, so you can fine-tune power delivery and decibel levels to your specifications. Parallelogram-shaped muffler Increased muffler volume over stock system, resulting in better throttle response and improved noise cancellation Light-weight muffler construction with carbon fiber end-cap CNC machined muffler bracket Reduced weight over OEM system Vertical tail-pipe divider splits the exhaust gases more evenly, for smoother flow, which improves mid-top power and throttle response Stainless steel header and tail-pipe Repack Kits, optional Inserts are available for all models Note: Installation of a new exhaust system may change your motorcycles fuel-air mixture requirements. Please consult the manufacturer directly with questions regarding any modifications that may need to be made during, or after installing their product. If a jet kit or EFI controller is recommended please see the Intake/Fuel section for products availableNote: Exhaust discoloration (bluing) is caused by engine conditions such as cam timing, fuel-air mixture, operating temperature, etc. It is not the result of defective manufacturing; therefore it is not covered by any warranty. See the Chems/Lubes section for products to help remove or prevent exhaust discoloration.