Yoshimura · RS-4
The Yoshimura SOUND INSERT KIT 94db RS-4 Muffler, 1.250" (INS-13-K) is a replacement low-volume insert kit designed for Yoshimura RS-4 mufflers. It’s intended for riders who need an optional insert solution on applications that call for different sound restrictions, with decibel reduction varying by application.
This kit is listed for Honda CRF450X 2019–2026, KTM 350SX-F 2013–2015, and KTM 350XC-F 2014–2015. For exact application confirmation, reference the fitment table and the insert chart noted by the manufacturer.
Built as a replacement low-volume insert kit for RS-4 mufflers, this Yoshimura insert provides an optional way to configure an RS-4 setup when different sound restrictions are required. The amount of decibel reduction depends on the specific application.
Yoshimura identifies this insert kit as non-spark arrested. This detail matters when selecting components for a specific riding area or requirement, so application confirmation should be handled using the insert chart referenced by the manufacturer.
The kit contents listed by Yoshimura include a low-volume insert tube, an end-cap collar, and a set screw. These parts are intended to support installation and securement of the insert in the RS-4 muffler configuration it is designed for.
Sound
INS-13-K is positioned in Yoshimura’s Replacement Service Parts line and is specifically described as a low-volume insert kit for RS-4 mufflers. It’s also presented as an optional kit for applications where a different sound restriction is needed, making it a targeted solution for riders working within application-specific sound limits.
Fitment
This Yoshimura sound insert kit is listed for Honda CRF450X 2019–2026, KTM 350SX-F 2013–2015, and KTM 350XC-F 2014–2015. Because fitment and results can depend on the exact application, the manufacturer recommends using the insert chart to confirm the correct match before installation.
Installation
The product page includes an installation PDF to assist with the setup process. Yoshimura also notes that decibel reduction depends on application, so confirming the appropriate insert and following the documented installation guidance helps ensure the kit is used as intended with the RS-4 muffler.
| Part Number | INS-13-K |
|---|---|
| Brand | Yoshimura |
| Product Line | Replacement Service Parts |
| Series | RS-4 |
| Shipping Weight | 0.5 lb |
| Barcode | 00840025914247 |
| Make | Model | Model Years |
|---|---|---|
| Honda | CRF450X | 2019–2026 |
| KTM | 350SX-F | 2013–2015 |
| KTM | 350XC-F | 2014–2015 |
Fitment as listed by Yoshimura for part number INS-13-K.
Instructions / What's Included (PDF)
Provided by Yoshimura. Opens in a new tab.
