*Product may vary by application
Emissions Compliance Declaration: QUALIFIED MANUFACTURER DECLARED "MODIFIED PART"
WARNING: Cancer and Reproductive harm - www.p65warnings.ca.gov
Description
After an impressive run of over two decades, 2025 brings an all-new Suzuki DR-Z4S/SM.
The new 398cc single cylinder water cooled engine is now fuel injected! We developed our RS-12 Race Series full system exhaust to enhance every aspect of the new DR-Z and the response was just what the doctor ordered. The RS-12 Race Series Full System packed substantial gains in performance adding 5.5% in hp @6,640rpm and 2.8% increase of torque @5,180rpm. These gains were made with our included/installed USFS spark arrestor SA-21-K! A custom stainless Yoshimura heat shield is included.
Yoshimura's RS-12 is proudly designed, developed and manufactured in Chino, California.
Weights:
Stock system: 17.8 lbs.
Yoshimura RS-12 full system: 10.6 lbs.
Sound levels: (Using J2825 standards) with installed spark arrestor.
2000 rpm
Stock: 74.4dB
RS-12: 90.4 dB
5000 rpm
Stock: 84.4 dB
RS-12: 93.4 dB
Sound Insert/Spark Arrester Options
|
Sound Level
|
Volume Insert | Spark Arrestor | Included |
 |
INS-32-K | No | |
 |
SA-21-K | Yes |
|
|
|
SA-20-K | No |
|
 |
No |
. . . . .
This product was designed to fit on a standard equipped motorcycle, as delivered from the factory. OE and aftermarket accessories not found on a bike as delivered from the factory may not be compatible with this product.
Attention international customers: This product was designed and tested to be compatible with vehicles in the U.S. marketplace only. Compatibility, including fitment and performance, may vary by marketplace.
Instructions / What's Included PDFYoshimura RS-12 Exhaust, INS-34K Insert & Fender Eliminator Review — 2025 Suzuki DR-Z4S
I installed the Yoshimura RS-12 full race exhaust on my 2025 Suzuki DR-Z4S, and I’ve been very pleased with it.
The difference in performance is noticeable. The bike definitely has more punch, and you can actually feel the extra power. The exhaust also has a really nice aggressive growl without sounding cheap or tinny. Installation was straightforward, and I had the entire system installed, cleaned up, and ready to go in about an hour.
One thing I really appreciated is that the exhaust already came with the spark arrestor installed in the tailpipe. Since I ride the DR-Z4S both on-road and off-road, that was a nice bonus and meant I didn't have to purchase it separately.
The full race system is loud, though. I love the sound when I'm riding, but I also don't want to piss off my neighbors every time I leave the house. I called Yoshimura directly to confirm that the INS-34K sound insert was available. They confirmed they had it in stock, and when I told them I would order it online, they even gave me a code for free shipping. Great customer service.
I installed the INS-34K this morning. Installation was extremely simple, and there is definitely a noticeable reduction in sound. The bike is still not quiet—which I wasn't expecting from a race exhaust—but it takes the edge off and makes the bike less obnoxious around town. My neighbors thank Yoshimura for that one!
I've only ridden about 10 miles with the INS-34K installed so far, but everything sounds and runs great. My plan is to use the insert when I'm cruising around the city and want to attract less attention, while still having the option of removing it when I want the full sound of the race system.
I also installed Yoshimura's fender eliminator/tail kit with the sequential rear turn signals. The sequential signals look fantastic and are a surprisingly premium-looking touch on a dual-sport bike.
My only criticism is the mounting tabs for the rear turn signals. With a passenger getting on or off the bike, it's possible for their foot to bump a signal and slightly bend the mounting tab, leaving the light sitting a little crooked. It was very easy to straighten the tab back out by hand, but I think this area could be a little more rigid.
Overall, I'm extremely pleased with the Yoshimura products on my DR-Z4S. The RS-12 delivers a noticeable performance improvement, sounds fantastic, and was easy to install. The INS-34K gives me a practical way to tone it down around town, and the sequential turn signals look excellent.
Great products, great fitment, and my experience dealing directly with Yoshimura was excellent.
This exhaust is everything I expected it to be. Effortless install, looks great, and sounds great. Couldn't be happier
Perfect install. I removed the baffle. 10/10 on sound. Noticeable performance increase.
100x100 good
Yosh full exhaust paired with 2 wheel dyno works ecu flash and air box mod brought this bike to life. Outstanding performance upgrade.
