Yoshimura · RS-12
The Yoshimura RS-12 Premium MX Muffler Repack Kit is a replacement service parts kit designed to refresh RS-12 off-road mufflers at the recommended maintenance interval. Yoshimura notes that off-road systems should be repacked after 6-8 hours of use, or after each Race, to help the exhaust continue performing as it was designed.
By replacing dirty, restrictive packing, the muffler can return to freer airflow from the motor, which helps restore lost power and improve exhaust sound. This kit is listed for a wide range of applications including select GasGas, Honda, Husqvarna, Kawasaki, KTM, Suzuki, Triumph, and Yamaha models and years shown in the fitment table below.
Materials
This kit includes Premium Packing Material intended to replace dirty packing that can restrict airflow. Yoshimura explains that maintaining fresh packing helps the exhaust perform the way it was designed, supporting freer airflow from the motor while improving sound quality after service.
Included
To support a complete repack service, the kit includes Rivets and a Rivet Band. These components are provided so the muffler can be reassembled properly after the packing is replaced, keeping the service straightforward and consistent with scheduled maintenance.
Installation
The kit comes with Decals for the Muffler sleeve and end-cap along with Repacking Instructions. With the included guidance, it is set up to help riders perform repacking at Yoshimura’s suggested intervals for off-road use.
Performance
Yoshimura states that off-road systems need to be repacked after 6-8 hours of use, or after each Race. Keeping up with that schedule is positioned as essential for the exhaust to perform the way it was designed. According to Yoshimura, dirty packing restricts airflow from the motor, which results in a loss of power and degradation of sound, while repacking allows for freer airflow that restores lost power and improves exhaust sound.
Included
This RS-12 repack kit is supplied as a complete refresh package for the muffler’s serviceable components. It includes Premium Packing Material along with Rivets and a Rivet Band for reassembly. Decals for the Muffler sleeve and end-cap are also included, plus Repacking Instructions to guide the process from disassembly through final installation.
Fitment
This repack kit is listed for specific model and year applications across multiple brands, including GasGas, Honda, Husqvarna, Kawasaki, KTM, Suzuki, Triumph, and Yamaha. Fitment varies by model and year, so the fitment table below should be used to confirm the correct application. An installation PDF is provided on the page for reference during the repacking process.
| Part Number | REPACK-RS12-MX |
|---|---|
| Brand | Yoshimura |
| Product Line | Replacement Service Parts |
| Series | RS-12 |
| Shipping Weight | 1 lb |
| Barcode | 00840025913134 |
| Make | Model | Model Years |
|---|---|---|
| GasGas | EX-250F | 2023 |
| GasGas | EX-350F | 2021–2023 |
| GasGas | MC-250F | 2021–2023 |
| GasGas | MC-350F | 2022–2023 |
| Honda | CRF300L | 2021–2026 |
| Honda | CRF300L-Rally | 2021–2026 |
| Husqvarna | FC250 | 2019–2027 |
| Husqvarna | FC250-Factory-Edition | 2022 |
| Husqvarna | FC350 | 2019–2027 |
| Husqvarna | FC450 | 2023–2027 |
| Husqvarna | FE350S | 2024 |
| Husqvarna | FE501S | 2024, 2026 |
| Husqvarna | FX350 | 2023–2025 |
| Kawasaki | KX250F | 2021–2026 |
| Kawasaki | KX250X | 2021–2026 |
| Kawasaki | KX450F | 2024–2026 |
| Kawasaki | KX450X | 2024–2026 |
| KTM | 250SX-F | 2019–2027 |
| KTM | 250SX-F-FACTORY-EDITION | 2022 |
| KTM | 250XC-F | 2019–2020, 2023–2026 |
| KTM | 350EXC-F | 2024 |
| KTM | 350SX-F | 2019–2027 |
| KTM | 350XC-F | 2019–2020, 2023–2026 |
| KTM | 450SX-F | 2023–2027 |
| KTM | 450SX-F-FACTORY-EDITION | 2022 |
| KTM | 500EXC-F | 2023–2026 |
| Suzuki | RM-Z250 | 2019–2026 |
| Suzuki | RM-Z450 | 2018–2026 |
| Triumph | TF250 | 2024–2026 |
| Yamaha | YZ250F | 2024–2026 |
| Yamaha | YZ450F | 2020–2025 |
Fitment as listed by Yoshimura for part number REPACK-RS12-MX.
Instructions / What's Included (PDF)
Provided by Yoshimura. Opens in a new tab.
