Yoshimura · RS-12
The Yoshimura SOUND INSERT KIT RS-12 Muffler, 1.375" is a replacement low-volume insert kit designed specifically for RS-12 mufflers. It’s intended for riders who need a different sound restriction option and want a service-part solution that matches the RS-12 series.
Fitment includes select Honda, Triumph, and Yamaha models listed in the fitment table below, including Honda CRF450R 2021–2026 and Yamaha YZ450F 2026–2027. This is a non-spark arrested insert kit, and decibel reduction will vary by application.
Built as a replacement low-volume insert kit for Yoshimura RS-12 mufflers. It’s also offered as an optional kit for applications that require different sound restrictions, helping tailor the exhaust note to specific needs depending on the application.
This insert kit is specified as non-spark arrested. It is intended for RS-12 muffler applications where a low-volume insert is desired, and where a spark arrestor is not part of the required configuration.
The kit includes the low-volume insert tube, an end-cap collar, and a set screw. These components are provided together as the service kit to support installation into compatible RS-12 muffler setups.
Sound
Yoshimura lists this kit in its Replacement Service Parts line for the RS-12 series, making it a focused solution for riders using RS-12 mufflers. It’s described as a low-volume insert kit and is also positioned as an option for applications that call for different sound restrictions, with results varying based on the specific motorcycle and setup.
Installation
An installation PDF is provided on the page to guide setup. The kit’s included parts consist of a low-volume insert tube, end-cap collar, and set screw, aligning with its role as a replacement insert kit for RS-12 mufflers.
| Part Number | INS-32-K |
|---|---|
| Brand | Yoshimura |
| Product Line | Replacement Service Parts |
| Series | RS-12 |
| Shipping Weight | 1 lb |
| Barcode | 00840025914292 |
| Make | Model | Model Years |
|---|---|---|
| Honda | CRF450R | 2021–2026 |
| Honda | CRF450R-S | 2023–2024 |
| Honda | CRF450RX | 2021–2026 |
| Triumph | TF250 | 2024–2026 |
| Triumph | TF450 | 2025–2026 |
| Triumph | TF450-C | 2025–2026 |
| Triumph | TF450-E | 2025–2026 |
| Triumph | TF450-X | 2025–2026 |
| Yamaha | YZ450F | 2026–2027 |
Fitment as listed by Yoshimura for part number INS-32-K.
Instructions / What's Included (PDF)
Provided by Yoshimura. Opens in a new tab.
