2019 marks a new quest for the Kawasaki brand to own the 450cc motocross class. By the looks of it, the new big bore green machine looks like a strong contender.

At Yoshimura, we saw an opportunity to make the new green offering live up to its potential. Power and torque is up across the entire range for both curves with the new KX! Max HP is up an incredible 3% and max torque is up 4.3%. The heart of the power is our RS-4 muffler with its Polyresonant Duplex front chamber and added overall volume helps make the 2019 KX450 come alive.

If you're serious - it's only Yoshimura. Proudly made in the USA!

• Pentagonal-shaped sleeve
• Front muffler cap functions as a polyresonant chamber which helps reduce noise
• Two-stage stepped baffle
• Carbon fiber end-cap
• Stainless tail-pipe

(1) Aluminum tailpipe

(1) Muffler assembly

(1) Rubber grommet

(1) Aluminum spacer

(1) Small exhaust spring

(1) 8mm Large washer

(1) Spring puller tool

(1) Wash plug

Instructions