Yoshimura's RS-4 FS Titanium Full System
Price: $945.00
Application: 2016-18 KTM 250 SX-F

What It Is

Yoshimura is well-known across the motocross community for producing exceptional power gains and great sounds, all while providing a trick aftermarket look to your bike. The KTM 250SX-F comes off the showroom floor with one of the strongest motors in the class, however, the power plant could use some more initial hit in the bottom. The Yoshimura RS-4 system provides buyers with a stylish titanium header and muffler, which is topped off with a carbon fiber end-cap. The goal for the crew over at Yoshimura was to provide some more power in the low-end roll, while at the same time maintaining the strong mid-to-top end power.



– Upon unboxing, we immediately noticed the lightweight feel of the Yoshimura system. Assembled, it is 0.7lbs lighter than stock.

– Yoshimura provides buyers with extra hardware for the exhaust system, as well as the necessary spacers, springs, etc.

– The RS-4 exhaust is a simpler two-piece system, versus the difficult stock three-piece system that forces the rear shock to be dropped when removing.

– The overall look of the titanium system matched up with the carbon fiber end-cap is incredible.

– The system gives the bike a deeper, more aggressive sound.

– Power is exceptionally stronger in the low-end, while even adding some gains towards the already great top-end. Overall, it’s a great enhancement to the KTM’s stellar engine.


– Although the titanium finish looks appealing, once heated up some leftover fingerprints can be stained onto the finish. Be sure to wipe the system down after it’s installed to prevent this from happening.

The Verdict

The KTM 250SX-F is an already exceptional machine, from its handling to its power curve. However, the Yoshimura RS-4 FS Ti-Ti system gives the bike that extra low-end roll, an aggressive sound, and even adds to the strong top-end.