Yoshimura · RS-12 · Full System
The Yoshimura RS-12 Race Series Exhaust System is a stainless full system built to sharpen the riding experience of the Honda CRF300L 2021–2026 and Honda CRF300L-Rally 2021–2026. Designed as a complete replacement system, it targets riders looking for a stronger pull and a more distinctive exhaust character while keeping the package lightweight.
Developed and built in Chino, Ca., the RS-12 is backed by manufacturer-reported testing and is shown with supporting media on the page, including a dyno chart, product video, and an installation PDF. Check the fitment table below to confirm the exact application details for this full system.
Materials
Built as a Full System in the RS-12 series, this Race Series Exhaust System is specified as stainless construction. It’s intended as a complete system upgrade for the CRF300L and CRF300L-Rally platforms listed in the fitment table, with a design focus on performance and sound character.
Performance
Yoshimura reports up to 6.8% more horsepower at 8. A dyno chart is shown on the page to support the published claim, helping riders evaluate the reported performance change in the context of the documented test results.
Engineering
Yoshimura’s product data highlights a lightweight approach for improved handling feel, listing the system at 9 lbs (vs. stock 12.3 lbs). That reduction is positioned as a benefit for agility and responsiveness when riding on mixed surfaces typical of the CRF300L and CRF300L-Rally.
Engineering
Positioned in Yoshimura’s Race Series Exhaust System lineup, the RS-12 is engineered as a full-system solution rather than an add-on. The manufacturer describes the system as engineered, developed and built in Chino, Ca., emphasizing a purpose-built approach for the CRF300L and CRF300L-Rally platforms covered here. Stainless construction is specified in the product data, aligning with the rugged use these dual-sport models typically see.
Performance
For riders choosing a full system primarily for output, the RS-12 includes a verified performance statement from the manufacturer. Yoshimura reports up to 6.8% more horsepower at 8. The page also includes a dyno chart and product video, allowing shoppers to review the provided supporting media alongside the manufacturer’s published claim.
Fitment
This RS-12 full system is listed for Honda CRF300L 2021–2026 and Honda CRF300L-Rally 2021–2026. Fitment is model- and year-specific, so the fitment table should be used to confirm application before purchase. For installation planning, an installation PDF is shown on the page, along with product photos and a video to help visualize routing, placement, and overall system layout.
Figures as reported by Yoshimura.
| Part Number | 123410S520 |
|---|---|
| Brand | Yoshimura |
| Product Line | Race Series Exhaust System |
| Series | RS-12 |
| System Type | Full System |
| Material | Stainless |
| Spark Arrester | Not included |
| Shipping Weight | 14 lb |
| Barcode | 00840025919488 |
| Emissions Compliance | QUALIFIED MANUFACTURER DECLARED "MODIFIED PART" |
| Make | Model | Model Years |
|---|---|---|
| Honda | CRF300L | 2021–2026 |
| Honda | CRF300L-Rally | 2021–2026 |
Fitment as listed by Yoshimura for part number 123410S520.
| Part Number | Type | Included With This System |
|---|---|---|
| SA-20-K | Spark Arrester | Installed |
| INS-34-K | Sound Insert | No |
Instructions / What's Included (PDF)
Provided by Yoshimura. Opens in a new tab.
