RS-4 Full Exhaust for CRF450X: Performance & Fit
By Yoshimura R&D of America, Inc. | Published: 2026-10-20
Category: Buying Guides
The Yoshimura RS-4 stainless full exhaust boosts CRF450X power and rideability. This guide explains its performance gains, trade-offs, and who should choose it.
Quick answer
The Yoshimura RS-4 stainless full exhaust is a top upgrade for the CRF450X, delivering broader power and improved rideability across off-road conditions. It's best for riders who want a durable, performance-focused system without the weight savings of titanium.
Why the RS-4 works for the CRF450X
Honda's CRF450X is a serious 450cc off-road machine, but its stock exhaust can leave power on the table. Yoshimura engineered the RS-4 system specifically to improve power in every area while making the bike easier to ride in varied terrain. The result is a more usable powerband that helps you tackle technical trails or open desert without constant clutch work.
The stainless steel construction with an aluminum muffler keeps the system durable and corrosion-resistant, a practical choice for riders who ride in mud, sand, or wet conditions. While it's heavier than a titanium option, the RS-4 stainless system offers a strong balance of performance and longevity at a lower price point.
Trade-offs to consider
The main trade-off is weight: stainless steel is heavier than titanium. If you're chasing every ounce for racing or extreme enduro, a titanium system like the RS-12 might suit you better. However, for most off-road enthusiasts, the RS-4's weight penalty is negligible compared to the power gains and durability.
Installation requires basic mechanical skills and tools. The full system replaces the header and muffler, so you'll need to remove the stock components and follow torque specs. Yoshimura provides a step-by-step guide, but if you're not comfortable with exhaust work, factor in professional installation costs.
Decision rules
- Power improvement: Choose the RS-4 if you want a noticeable power increase across the rev range, especially in mid-to-top end, without sacrificing low-end tractability.
- Durability: Stainless steel with an aluminum muffler offers excellent corrosion resistance and long life, ideal for riders who ride in wet or muddy conditions.
- Weight: The RS-4 stainless system is heavier than titanium options. If weight savings are critical, consider a titanium system like the RS-12. If you prioritize weight savings, look at titanium alternatives.
- Price: At $591.57 (down from $939.00), the RS-4 offers strong value for a full exhaust system that delivers proven performance gains.
- Installation: Full system installation requires removing the stock header and muffler. Follow Yoshimura's instructions and torque specs. Professional installation is an option if you're not confident. Check your mechanical comfort level before purchasing.
Product facts
- CRF450X 19-26 RS-4 Stainless Full Exhaust, w/ Aluminum Muffler: Yoshimura designed the RS-4 system to improve power in every area while making the CRF450X easier to ride in a variety of off-road conditions. This means you get a broader, more controllable powerband that helps you maintain momentum on technical trails and reduces the need for constant shifting.
CRF450X 19-26 RS-4 Stainless Full Exhaust, w/ Aluminum Muffler
Who should buy the RS-4?
Best for
- Riders who want a durable, performance-oriented exhaust for trail riding, desert racing, or general off-road use.
- Owners who value a proven power upgrade at a competitive price without needing the lightest possible system.
Not for
- Riders who prioritize absolute weight savings and are willing to pay more for a titanium system.
- Those who need a slip-on only; the RS-4 is a full system that replaces the header and muffler.
