Yoshimura RS-12 Full System Exhaust - Stainless Steel - 225860S520

The 2025 Honda CRF450R is here and has undergone significant changes to the overall package. Hunter Lawrence found the changes so inspiring that led him to compete with the new machine in the last three rounds of AMA Pro Motocross.

The newest CRF450R boasts an all-new new chassis, airbox and ECU configuration. Yoshimura's engineering and development team has had their nose to the grindstone with Team Honda HRC to squeeze every drop of performance out of the new 450. With the new RS-12 Signature Series full system, they achieved a max HP gain of 3.7% over stock while the max torque gain came in at 1.3%.

Hydroformed Muffler:

This is the first of a new generation RS-12 profile exhaust system featuring weight reducing hydroformed technology. This technology allows to maximize available space for a tailored fit while minimizing material usage. Hydroforming removes many of the limitations of conventional metal forming methods allowing for a stronger and lighter muffler. This new sleeve also incorporates a deep draw one-piece resonator further improving durability.

Hydroformed Header Primary:

Improved performance due to exact matching of the oval exhaust port, with a smooth internal transition from oval to round. Increased durability from a reduction in welded connections. Improved fit from the exact repeatability of hydroform process.

Carbon Faced Machined Joint:

The new Carbon Faced Machined Joint no longer requires the use of anti-seize. This is accomplished by impregnating the surface of the stainless steel joint with carbon atoms. The result is a reduction in wear over the life of the joint by reducing friction.

Header Resonator:

Developed in cooperation with the Honda HRC Team, the header resonator isn't just there for looks, it allows to maximize power across the spectrum, while enhancing rider connectivity.

Cast Manifold:

Benefit - Increased strength, durability, easier installation and removal.

The new RS-12 for the 2025 Honda CRF450R/RX also comes with an INS-32-K sound insert installed. This insert not only produces an ear pleasing exhaust note, it also makes the best power for the new Honda.

Installation Instructions (1.50 MB)