PRODUCT TEST: FMF Racing Factory 4.1 RCT TRX450R Exhaust

WHAT IT IS:
A quality aftermarket exhaust is commonly the commonly the first step towards first step towards unlocking untapped unlocking untapped power in a stock ATV or power in a stock ATV or motorcycle. FMF has been at the motorcycle. FMF has been at the forefront of performance exhausts for forefront of performance exhausts for many years, and the 4.1 RCT is the many years, and the 4.1 RCT is the result of 43 years’ worth of dedication to result of 43 years’ worth of dedication to the industry. The 4.1 RCT is the same the industry. The 4.1 RCT is the same top-of-the-line-series FMF exhaust that top-of-the-line-series FMF exhaust that the factory race teams use for SX and the factory race teams use for SX and MX nationals. FMF had not yet produced MX nationals. FMF had not yet produced this latest technology system for the this latest technology system for the Honda ATV, and they used our test Honda ATV, and they used our test machine for testing and fitment. The 4.1 RCT is the most advanced exhaust that you can buy from FMF.

WHAT’S IT MADE OF:
The Factory 4.1 RCT is made completely of top-quality, aerospacegrade materials and manufactured to exacting tolerances/specifications in FMF’s massive Southern California factory. The version we got features a blue-anodized titanium muffler can with a lightweight carbon fiber end cap. The mid-pipe is also manufactured from the same proprietary blend of alloy-grade titanium. Our test exhaust featured a stainless steel MegaBomb header, but it is also available in titanium. The polished stainless steel is both unbelievably durable and lightweight.

FEATURES:
The Factory 4.1 RCT uses FMF’s latest Resonance Chamber Technology (RCT), both internally and externally, to keep sound to a minimum and power output maximized. The 4.1 RCT is also output maximized. The 4.1 RCT is also shorter and less susceptible to crash shorter and less susceptible to crash damage. This shorter design is part of damage. This shorter design is part of FMF’s Factory Forward Engineering that keeps the muffler closer to the frame, therefore centralizing its mass. The super-trick MegaBomb header uses incredible advances in science to boost performance up to 3 horsepower from a slip-on muffler by itself. An even bigger feat is that the MegaBomb actually reduces noise levels by 1.5 decibels in the process. The MegaBomb technology produces more low-end power and offers broader midrange to top-end power gains. The MegaBomb is said to produce long-header torque with short-header over-rev.

INSTALLATION:
Installation is as simple as it gets. Remove your stock exhaust by removing the two header nuts and two muffler mounting bolts. Replace the exhaust header crush gasket and install the new pipe. FMF supplies new hardware and a billet aluminum spacer. As with any exhaust system, you will need to re-jet to compensate for additional flow. FMF can give you jetting recommendations or even supply you with the proper jets.

HOW DOES IT PERFORM?
The 4.1 RCT gives the 2006–2014 TRX450ER a really smooth and extremely rideable power curve. We added nothing but the new FMF RCT exhaust, appropriate jetting and removed the airbox lid for nearly 43 horsepower on the dyno. This is almost a 7-horsepower increase over the stock machine’s 36 horsepower. The latemodel Honda will show an even more impressive power gain if you couple exhaust/ jetting with a better cam. The stock cam is extremely detuned for emission reasons, and an HRC, Web Cam or Hot Cam with the right exhaust can get you upwards of the exhaust can get you upwards of the 50-horsepower mark in a hurry. 50-horsepower mark in a hurry.

WHO’S IT FOR:
The 4.1 RCT is for anyone who wants a top-of-the-line performance exhaust that will look great, reduce weight and probably last a lifetime. This is a greatperforming, lightweight exhaust system for any enthusiast who appreciates fine workmanship and spaceship-type build materials. Any racer, especially one who needs to meet strict soundtesting regulations, will also appreciate the amazing overall performance and broad power curve. The 4.1 RCT may be the perfect exhaust for the guy who demands the best, regardless of cost.

THE VERDICT:
This is the nicest pipe we’ve ever had on a TRX450R. The materials and workmanship are out of this world, and you almost feel bad riding it and getting it dirty. It sounds great, appears to hold up really well, and weighs next to nothing. On the other hand, the 4.1 RCT is also the most expensive ATV exhaust we’ve ever tested. At $800 with a stainless header or $900 with a Ti header, the 4.1 RCT is a serious investment. In fact, we’ve bought a few complete TRXs for around twice the price of this exhaust. With that said, if you want the best exhaust money can buy, your search just might be over.

CONTACT: www.fmfracing.com or call them at (310) 631-4363
RATING: ★★★★
PRICE: $799