Yoshimura · RS-4
The Yoshimura SOUND INSERT KIT 94db RS-4 Muffler, 1.500" is a replacement low-volume insert kit designed specifically for Yoshimura RS-4 mufflers. It’s intended for riders who need a lower-volume setup for certain applications and sound restrictions, with decibel reduction varying by application.
This kit is listed for Honda CRF250R 2010–2013, Honda CRF450R 2009–2012, Husqvarna Norden-901 2022–2023, KTM 350EXC-F 2011–2015, KTM 350SX-F 2011–2012, KTM 790-ADVENTURE 2019–2020, KTM 890-ADVENTURE 2021–2023, Suzuki RM-Z250 2010–2014, Suzuki RM-Z450 2008–2014, Suzuki RMX450Z 2010–2011, Yamaha YZ250F 2007–2013, and Yamaha YZ450F 2010–2014. Please reference the fitment information shown on the page to confirm the correct application.
Sound
Built as a replacement low-volume insert kit for Yoshimura RS-4 mufflers, this setup is aimed at riders who want to change sound output without replacing the entire muffler assembly. It is also offered as an optional kit on applications that require different sound restrictions.
Installation
This insert kit is identified by Yoshimura as non-spark arrested. For riders who need to meet specific equipment requirements, it is important to verify insert style and intended use before installation, using the insert chart and the application details provided on the product page.
Included
The kit includes the low-volume insert tube, an end-cap collar, and a set screw. These included pieces are intended to provide the components needed for installing the insert into the RS-4 muffler configuration listed for the applicable models.
Fitment
This insert kit is listed across a wide range of off-road and adventure platforms, including multiple years of Honda CRF, Suzuki RM-Z and RMX, Yamaha YZ-F, KTM EXC-F and SX-F, plus Husqvarna Norden-901 and KTM 790-ADVENTURE and 890-ADVENTURE models. To avoid mismatches, fitment should be confirmed using the fitment information and the insert chart referenced on the page.
Installation
With an installation PDF provided on the product page, this insert kit is supported with documentation to help guide setup. The included insert tube, end-cap collar, and set screw are intended to work together as a complete service kit, making it suitable for replacement needs or for switching to a lower-volume configuration on compatible RS-4 muffler applications.
| Part Number | INS-14-K |
|---|---|
| Brand | Yoshimura |
| Product Line | Replacement Service Parts |
| Series | RS-4 |
| Shipping Weight | 0.45 lb |
| Barcode | 00840025908741 |
| Make | Model | Model Years |
|---|---|---|
| Honda | CRF250R | 2010–2013 |
| Honda | CRF450R | 2009–2012 |
| Husqvarna | Norden-901 | 2022–2023 |
| KTM | 350EXC-F | 2011–2015 |
| KTM | 350SX-F | 2011–2012 |
| KTM | 790-ADVENTURE | 2019–2020 |
| KTM | 890-ADVENTURE | 2021–2023 |
| Suzuki | RM-Z250 | 2010–2014 |
| Suzuki | RM-Z450 | 2008–2014 |
| Suzuki | RMX450Z | 2010–2011 |
| Yamaha | YZ250F | 2007–2013 |
| Yamaha | YZ450F | 2010–2014 |
Fitment as listed by Yoshimura for part number INS-14-K.
Instructions / What's Included (PDF)
Provided by Yoshimura. Opens in a new tab.
