Brand new from KTM and Husqvarna for 2019 are re-vamped 250 SX-F / FC250 and SX-F 350 / FC350.

Both the 250 and 350 make good HP and torque in stock form, but nevertheless we went to work to improve power in every RPM range on these twin race machines and the gains we were able to attain with our RS-4 are quite impressive.

We wound up with the 250 peak HP at 6.6% and a big gain of peak torque of 14.2% The 350 was even more impressive with a peak HP gain of 10.2% and peak torque gain of 7%. The work horse for much of this performance is our RS-4 muffler. With its Polyresonant Duplex front chamber to add overall volume, and the special stepped two-stage baffle configuration that reduces sound without restricting performance. These Austrian 250 and 350 race machines are ready for the top of the podium now! Spark arrestor available separately.

If you’re serious – it’s only Yoshimura. Proudly made in the USA!