The Suzuki RM-Z450 was heavily revised for 2018 and was praised for having a better fork than in years past while maintaining good cornering ability. The engine was mildly improved with a bit more top-end power than the previous-generation model, yet it retained its controllable low-end power that helps make it easy to ride. But we still desired more overall power from the yellow machine, mainly in the midrange and top-end. To try and coax out more power, we procured an FMF Factory 4.1 RCT titanium full exhaust system.

The Factory 4.1 RCT uses FMF’s Resonance Chamber Technology (RCT) both internally and externally. The Southern California company was able to achieve a shorter overall length for the entire system, thereby making it less susceptible to crash damage and complementary to FMF’s Factory Forward Engineering, which moves the muffler closer to the engine to help centralize mass. To top it off, the system comes in an eye-catching blue-anodized finish and is equipped with a carbon-fiber end cap.

The FMF Factory 4.1 RCT full titanium exhaust system is a three-piece setup, whereas the stock unit is a two-piece.Andrew Oldar

The first thing we did after unboxing the Factory 4.1 RCT system was weigh it. We could tell by holding the muffler and header pipe that they were significantly lighter than the stock system and, sure enough, the FMF saved a whopping 4 pounds over the OEM unit. The stock exhaust weighed in at 9.2 pounds, and the FMF at 5.2 pounds. Installation was a breeze as the Factory 4.1 RCT three-piece system lined up just right with each of the mounting locations. Like we do when installing any aftermarket exhaust system, we used anti-seize on the joining locations to ensure easy removal when we have to take off the pipe.

The header pipe is FMF’s MegaBomb and is made of titanium.Andrew Oldar

When kicking the Suzuki to life with the FMF installed, the RM-Z450 has a noticeably deeper and throatier tone yet isn’t loud or obnoxious at high rpm. On the track, the Factory 4.1 RCT delivers increased midrange and top-end power, yet retained the Suzuki’s easy-to-manage low-end with the over-rev being comparable to stock. The improved midrange and top-end filled in the parts of the powerband we felt were lacking with the stock system and made the power delivery feel more linear as well.

The muffler is FMF’s Factory 4.1 RCT unit, which has a blue-anodized finish and a carbon-fiber end cap.Andrew Oldar

We are very impressed with the improvements the FMF Factory 4.1 RCT full titanium exhaust system delivered on the latest-generation (2018–’19) Suzuki RM-Z450. It provided increased power, decreased weight, and made a better, throatier sound. The titanium system we tested runs a retail price of $899.99; FMF also offers the same system with a stainless steel header pipe, aluminum muffler, and carbon-fiber end cap for $699.99 for those looking for the same power increase at a lower price tag but with slightly less weight savings. If you’re looking to squeeze more power out of your RM-Z450 while cutting weight and improving both the sound and look, the FMF Factory 4.1 RCT full titanium exhaust system is an excellent option.

The Factory 4.1 RCT full system saved 4 pounds over the stock unit and increased the midrange and top-end power of the RM-Z450.Andrew Oldar