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FMF Factory 4.1 RCT Full Exhaust System

(4 reviews)

Item: 327452

$809.99 – $1237.49

Select Your Vehicle - Fitment Guaranteed

FMF Factory 4.1 RCT Full Exhaust System


FMF's Factory 4.1 RCT Full Exhaust System incorporates the latest in RCT (Resonance Chamber Technology) both internally and externally. The core's shape lowers decibels without compromising power output. In addition, FMF designed the exhaust specifically to achieve a shorter overall length so as to be less susceptible to crash damage. Complementary to FMF's Factory Forward Engineering, the muffler is also moved closer to the motor to centralize mass and improve handling. The Factory 4.1 RCT is constructed from only aerospace grade materials that meet the California company's exacting specifications.

Each exhaust comes with FMF's proprietary MegaBomb header. The science behind the MegaBomb header actually reduces noise levels by as much as 1.5 dB when compared to conventionally-shaped headers to keep race and track officials happy. In addition, the headers are designed to produce more low end to mid range gains as well as broadening out the mid to top end power gains when compared to the stock exhaust layout.

  • Massive power gains throughout the entire RPM range
  • MegaBomb header for the ultimate in power output
  • Huge weight savings when compared to the stock exhaust
  • Fabricated using the highest quality proprietary blend of alloy grade materials
  • FMF RTS (Rapid Tuning System) makes for easy exhaust insert changes
  • Includes USFS-approved spark arrestor and quiet insert
  • Comes with all required mounting hardware and easy-to-follow installation instructions
  • Made in the USA
Specification Details
Color Varies (make selection above)
Country of Origin USA
Finish Varies (make selection above)
Header Varies (make selection above)
Header Construction Varies (make selection above)
Mid-Pipe Varies (make selection above)
Muffler End Cap Carbon Fiber
Muffler Sleeve Varies (make selection above)
USFS Approved Spark Arrestor Yes

Vehicle Fitment


Fitment is guaranteed or your money back plus free return shipping.
Don’t waste time installing a product that doesn't fit. We worked hard ensuring that this product is an exact fit on the vehicles listed below.

Gas Gas
  • EC 250F 2021-2022
Honda
  • CRF250R 4-Stroke 2022-2024
  • CRF450R 2021-2025
  • CRF450RX 2021-2025
Husqvarna
  • FC 250 2019-2022
  • FC 350 2019-2022
  • FC 450 2018-2022
  • FE 250 2020-2022
  • FE 350 2020-2022
  • FE 450 2020, 2023
  • FE 501 2020-2023
  • FX 350 2019-2022
  • FX 450 2019-2022
KTM
  • 250 SX-F 2019-2022
  • 250 XC-F 2019-2022
  • 350 SX-F 2019-2022
  • 350 XC-F 2019-2022
  • 350 XCF-W 2021-2022
  • 450 SX-F 2019-2022
  • 450 XC-F 2019-2022
  • 500 XCF-W 2020-2022
Kawasaki
  • KX250 4-Stroke 2019-2024
  • KX250X 4-Stroke 2021-2024
  • KX450 4-Stroke 2019-2024
Suzuki
  • RM-Z250 2019-2025
  • RM-Z450 2018-2025
Yamaha
  • WR250F 2020-2024
  • WR450F 2019-2020
  • YFZ450R ATV 2009-2023
  • YFZ450X ATV 2010-2011
  • YZ250F 4-Stroke 2019-2025
  • YZ250FX 4-Stroke 2020-2024
  • YZ450F 2018-2025
  • YZ450FX 2019-2025

Customer Reviews

Write Review

Very nice

By   on  Verified Purchaser

Very nice, came in perfect condition.


FMF RCT

By   on  Verified Purchaser

We put this on our 2019 yfz450r and absolutely woke that thing up! Definitely worth every dime, and the guys here at parts giant super helpful getting me everything I needed to get it on right!


bad***!

By   on  Verified Purchaser

Worth every dollar!


FMF! Enough said!

By   on 

I have a 2015 Crf450r I bolted this up and she rips! Nice and loud, the throttle response is super crisp. You can’t beat it.


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Questions & Answers

Ask Question

Is fuel optimizer needed with 4.1 on 2019 yfz 450r

Yes, we would recommend adding a fuel tuner to be used with the system to get the most performance out of it.

By Andy
Answer Question

Will this husky 450 kit fit on my 2015 Husqvarna FE 501?

FMF went from manufacturing complete kits to an a la carte part number system. So, for most bikes, including the 2015 Husqvarna FE 501 - you have to purchase the header and the muffler separately. To get a full exhaust for your bike, choose your exact model from our FMF Stainless Steel MegaBomb Header and FMF Factory 4.1 RCT SL Slip-On Exhaust pages and you'll get everything you need!

By Staff
Answer Question

2010 Yamaha YFZ450R ATV. Can I get the mega bomb instead of the power bomb?

Once you select your machine from our fit guide, you'll be given the option of choosing which header you want for ATV.

By Staff
Answer Question

So this price listed is for the header and muffler in the blue? not just the muffler

i have a 2018 RMZ450

For the RM-Z450 FMF Factory 4.1 exhaust, if you were to select the muffler that has a titanium sleeve with carbon fiber end cap, you'd receive a complete exhaust system, header to muffler, with a blue muffler sleeve.

By Staff
Answer Question

So this is full exhaust and it does fit yfz450r 2017

If you were to choose the 2017 Yamaha YFZ450R ATV FMF exhaust from our fit guide, you'd receive the correct exact to fit that machine. We guarantee it!

By Staff
Answer Question

I have a 2017 Yamaha YFZ450R ATV. Does this exhaust system have any different colors or is it just blue?

As of this writing, FMF's exhaust for the YFZ450R is only available with a blue titanium sleeve and carbon fiber end cap.

By Staff
Answer Question

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