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FMF Factory 4.1 RCT SL Slip-On Exhaust

(3 reviews)

Item: 327248

$269.99 – $719.99

Select Your Vehicle - Fitment Guaranteed

FMF Factory 4.1 RCT SL Slip-On Exhaust


FMF's Factory 4.1 RCT SL slip-on muffler 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 muffler 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. Each FMF Factory 4.1 RCT slip-on muffler is constructed from only aerospace grade materials that meet the California company's exacting specifications.

  • Massive power gains throughout the RPM range
  • Huge weight savings when compared to the stock muffler
  • 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 94 dB sound insert
  • Fits OEM or FMF headers
  • Comes with all required mounting hardware and easy-to-follow installation instructions
  • Made in the USA
Specification Details
Color Varies (make selection above)
Configuration Varies (make selection above)
Country of Origin USA
Finish Varies (make selection above)
Mid-Pipe Varies (make selection above)
Muffler End Cap Varies (make selection above)
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.

Beta
  • 350 RR Enduro 2020
  • 390 RR Enduro 2020
  • 430 RR Enduro 2020
  • 480 RR Enduro 2020
Gas Gas
  • EC 250F 2021-2022
Honda
  • CRF125F 2019-2021
  • CRF125F Big Wheel 2019-2021
  • CRF250R 4-Stroke 2022-2024
  • CRF250RX 4-Stroke 2022-2024
  • CRF450R 2021-2022
  • CRF450X 2005-2009, 2012-2017, 2019-2024
  • TRX450ER Sportrax 450ER 2006-2014
  • TRX450R Sportrax 450R 2004-2014
Husaberg
  • FE 350 2013-2014
  • FE 501 2013-2014
Husqvarna
  • FC 250 2014-2022
  • FC 350 2014-2022
  • FC 450 2014-2022
  • FE 250 2014-2022
  • FE 350 2014-2022
  • FE 450 2015-2020
  • FE 501 2014-2023
  • FX 350 2017-2022
  • FX 450 2017-2022
KTM
  • 250 EXC-F 2017-2018
  • 250 SX-F 2007-2022
  • 250 XC-F 2007-2022
  • 250 XCF-W 2008-2016
  • 350 EXC-F 2012-2019
  • 350 SX-F 2011-2022
  • 350 XC-F 2011-2022
  • 350 XCF-W 2012-2016, 2021-2022
  • 400 XC-W 2009-2010
  • 450 EXC 2009-2011
  • 450 EXC-F 2017-2018
  • 450 EXC-R 2008
  • 450 SMR 2007-2009
  • 450 SX-F 2007-2022
  • 450 XC 2007
  • 450 XC-F 2008-2009, 2013-2022
  • 450 XC-W 2009, 2012-2016
  • 450 XCR-W 2008
  • 500 EXC 2012-2016
  • 500 EXC-F 2017-2019
  • 500 XC-W 2013-2016
  • 500 XCF-W 2020-2022
  • 505 SX-F 2008
  • 505 XC-F 2008-2009
  • 530 EXC 2009-2011
  • 530 EXC-R 2008
  • 530 XC-W 2009
  • 530 XCR-W 2008
Kawasaki
  • KLX140 2008-2020
  • KLX140G 2017-2020
  • KLX140L 2008-2020
  • KLX140R 2021-2022
  • KLX140R F 2021-2022
  • KLX140R L 2021-2022
  • KX250 4-Stroke 2019-2024
  • KX250F 4-Stroke 2009-2018
  • KX250X 4-Stroke 2021-2024
  • KX450 4-Stroke 2019-2023
  • KX450F 2009-2018
Suzuki
  • RM-Z250 2019-2024
  • RM-Z450 2011-2024
Yamaha
  • WR250F 2015-2024
  • WR450F 2016-2021
  • YFZ450R ATV 2009-2023
  • YFZ450X ATV 2010-2011
  • YZ250F 4-Stroke 2010-2024
  • YZ250FX 4-Stroke 2015-2024
  • YZ450F 2014-2024
  • YZ450FX 2016-2024

Customer Reviews

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Best purchase yet

By   on  Verified Purchaser

Best purchase yet for my dirt bike it looks killer with it on there. Somehow it was shipped to me in 1 day can't ask for no more, good quality parts and good customer service.


Fmf 4.1

By   on  Verified Purchaser

Highly recommend, good prices, good quality and fast shipping. Love this exhaust, best purchase yet.


FMF & Happy!

By   on  Verified Purchaser

My FMF showed up on time and was not missing anything I needed. Sound is great and increased performance.


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Questions & Answers

Ask Question

will this fit a 2023 crf250r

Yes, so long as you choose the correct year/make/model bike before adding to your cart, you would receive the correct slip-on for that bike.

By Andy
Answer Question

Will this fit a 2011 yz450f

Yes, as long as you choose a 2011 YZ450F when adding to your cart and you have a stock or FMF header, this would fit that bike.

By Andy
Answer Question

Will this fit on a husqvarna fc 250?

Yes, we do indeed have the FMF Factory 4.1 RCT SL exhaust for the Husqvarna FC 250. Just choose your exact machine from our fit guide and you'll be all set!

By Staff
Answer Question

I have a 2013 KTM 450 XC-F, will this fit?

Yes, if you were to select the 2013 KTM 450 XC-F FMF Factory 4.1 RCT SL Slip-On Exhaust from our fit guide, you'd receive the correct muffler to fit your bike.

By Staff
Answer Question

2015 yamaha yz250f

The year seems to be missing from the drop down menu. Does this fit the 2015 YZ250F?

FMF certainly does make a muffler to fit your Yamaha. If you were to select the 2015 Yamaha YZ250F 4-Stroke FMF Factory 4.1 slip-on muffler from our fit guide, you'd receive the correct exhaust for your machine.

By Staff
Answer Question

Will this fit a Yamaha WR250F 2015

Yes, if you were to choose the 2015 Yamaha WR250F FMF Factory 4.1 RCT SL Slip-On from our fit guide, you'd receive the correct WR250F exhaust to fit your machine!

By Staff
Answer Question

Will this fit a 2016 KX250f?

Yes, if you were to choose the 2016 Kawasaki KX250F exhaust from the fit guide that's immediately to the right of the main image, you'd receive the correct muffler to fit your machine.

By Staff
Answer Question

Will this fit a 2001 drz400?

FMF only offers a Powercore 4 and a Q4 muffler to fit the 2001 Suzuki DR-Z400 at this time.

By Staff
Answer Question

This pipe fits on ktm 500 exc 2015 ??? Thanx :)

Just be certain to select the appropriate model at checkout "2015 KTM 500 EXC" and you would have no issue installing this muffler to the 2015 KTM 500 EXC.

By Staff
Answer Question

do they have one of these for a 2015 WR450F

Unfortunately, FMF doesn't produce a Factory 4.1 RCT SL slip-on muffler to fit the 2015 Yamaha WR450F. Currently, FMF makes two different exhausts to fit your machine: FMF Q4 Hex Slip-On Exhaust for the 2015 Yamaha WR450F and 2015 Yamaha WR450F FMF PowerCore 4 Hex Slip-On Exhaust

By Staff
Answer Question

is this made out of titanium ?

Once you select your machine from our fit guide, you'll be presented with the muffler sleeve option. For many bikes, you can choose from an FMF aluminum sleeve with FMF carbon fiber tip, titanium sleeve with FMF carbon fiber tip or titanium sleeve with titanium tip. The options that you see will determine what kind of mufflers sleeve you would receive. Mind you, not all machines have all the options, so for some bikes, you may only be able to select one type of muffler sleeve.

By Staff
Answer Question

The ktm excf 500, will it fit the 2018 500?

Yes, if you were to choose the 2018 KTM 500 EXC-F FMF muffler from our fit guide, you'd get the correct FMF muffler to fit the big-bore KTM motorcycle!

By Staff
Answer Question

Will it fit a 2018 Suzuki 450 RMZ

If you were to choose the 2018 Suzuki RM-Z450 FMF Factory 4.1 RCT exhaust from out fit guide, you'd certainly receive the right FMF pipe to fit your bike!

By Staff
Answer Question

Will this fit a wr250r?

Unfortunately, FMF doesn't produce a Factory 4.1 RCT to fit any WR250R models. The only mufflers we have on hand to fit that machine from FMF come in the form of the WR250R Q4 Slip-On Exhaust or the PowerCore 4 Slip-On Exhaust for the Yamaha WR250R.

By Staff
Answer Question

Will this pipe fit a 2011 kx450f

Yes, FMF does make a Factory 4.1 RCT SL slip-on muffler to fit the 2011 Kawasaki KX450F. Simply choose your make, year and model from the dropdown fit guide that's to the right of the main image on our website and we'll get the correct FMF exhaust on its way to your quickly!

By Staff
Answer Question

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