Review by Bryan Wallace/ Photos by Michael Lindsay
Since Vital MX received their 2014 YZ450F, I was lucky enough to grab it for the past few months to pound out some laps, and put in the hours. With all this time on it, I found myself wanting to see if there was anything to be gained in the power department. FMF had an early jump on development with the new YZ450F, thanks to their partnership with JGR. So when I was handed this and told to try it out, I was excited to see if all the testing would shine through.
FMF 4.1 RCT Features:
- Tuned exhaust with optimized core specifications for each application.
- Patented core shape lowers sound level while maintaining maximum power output.
- Quieter than stock.
- Huge weight savings with Titanium models.
- New RTS (Rapid Tuning System) makes for easy sound insert changes as well as adding US Forestry Approved Spark Arrestor.
- RCT exhaust can/mid-pipe can be used with a FMF or stock head-pipe.
- Mega-Bomb head pipe produces long header like torque but with short header over-rev.
- Starting Price $899.99 ($1049.99 as tested).
- Comes with 94db insert.
Since Yamaha went with their reverse cylinder design, instillation of an exhaust can be... a bit interesting. When I was unboxing the FMF system that thought kept running through my mind, wondering if it would all slide into place like a puzzle, or if I was going to be grabbing a mallet to help it along. FMF has done their homework though when it comes to fitment, as their system goes together even easier than the stock one. With the way Yamaha routes their exhaust, the cans end fairly early and are tucked in behind side plate. Thanks to the blue anodized can and carbon end cap, the FMF stands out a bit more, which is always a plus when you're spending the extra cash for the higher end systems. After all, who wants it to look stock?
On the Track:
An exhaust can look trick and even make great power on a dyno, but on the track is where it really matters. The stock YZ450F is one of the strongest 450s I've ridden, but it isn't the most rideable. It hits very hard low-to-mid, hard enough to wear you out after a few laps when pushing. Then it goes a bit flat up top, causing you to short-shift and fall right back into that hard-hitting power. Instantly I noticed the FMF changed this up a bit by spreading the power out. It upped the torque at an even lower RPM, meaning even though it's making more power, it's actually starting so low it carries even better into the midrange. Up top, there are some gains as well, as it continues to pull a bit farther than stock without going as flat. This spread of power made the bike quite a bit easier to ride when the track was getting wore down and the laps were dragging on.
Running a Titanium system always leaves a bit of a worry when it comes to durability, but FMF seems to have this area dialed as well. In the last five months, I've put around 25 or so hours on this exhaust and outside of a few scratches on the can (which are due to the cut of the side-plate), it has held up very well. With the exhaust wrapping around right along your legs on both sides, burning your pants can be an issue. FMF has tabs on their head-pipe on each side, so you can re-use the guards off the stock system. It made the system look a bit more stock, which I didn't care for, but I'll take the trade-off, considering my pants haven't been melted thanks to those guards.
The Last Word:
The improvements the FMF system made were a welcomed addition. It seems to be getting harder and harder for exhaust companies to make gains and not lose power at another point. On top of that, being able to make power that is usable and makes the bike easier to ride, which is a huge plus considering how much time I spend on this bike. I know that Titanium systems are always a bit pricey, but FMF's current Yamaha systems are one of their most expensive pipes. For most, a stainless/aluminum would probably be easier on their wallet but with this much head pipe length, the Titanium system does drop a fair amount of weight.
Vital MX Rating:
For more information on FMF's 4.1 RCT Exhaust System, or to check out their other products go to FMFracing.com.
About the Test Rider:
Bryan Wallace was born and raised in New Jersey by a family that owned a motorcycle shop. Growing up chasing the dream of becoming a professional motocross racer has led him around the country racing and landing him in California, where he now maintains tracks for some of the sport's top riders. When he isn't fixing tracks, he is ripping them up, and lining up for any national he can get to.