FMF Factory-4.1 RCT Aluminum Silencer with Carbon End Cap

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FMF Factory-4.1 RCT Aluminum Silencer with Carbon End Cap
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FMF Factory-4.1 RCT Aluminum Silencer with Carbon End Cap

Our Price: $331.99$404.99

MSRP: $349.99 - $449.99 - You save up to $45.00 (10% off)

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Additional Videos

FMF Factory | Inside Look

FMF Factory 4.1 RCT Sound Bite

RM YouTube Channel

Details

    If you're a rider looking for a silencer that's packing stellar looks and increased performance from a staple brand in motorsports, the FMF Factory 4.1 RCT Aluminum Silencer with Carbon End Cap is an option that we think sits close to the top of the class.

    FMF distinguishes their 4.1 RCT from other silencers from the start by using premium materials and a refined design developed over years of industry experience. Features like FMF’s unique Resonance Chamber Technology™ (RCT), a specialized chamber that sits at the front of the slip-on, lowers your exhaust decibel level so it complies with FIM 2M max sound tests and the stringent AMA sound requirements so you can get onto any trail and into any race where noise level regulations are enforced.

    While the RCT lowers sound, what's better is that it won't eat up your bike's power either. In Fact the RCT chamber design refines and enhances exhaust pressure to give your bike gains throughout the rpm range. Power increases are tunable as well with the end cap housing FMF's new Rapid Tuning System (RTS) that lets you swap between race tips (sold seperately) and the 94 db Quiet Core insert. With this level of performance and versatility FMF's Factory 4.1 RCT Silencers really do serve as an excellent option for all types dirt and off-road riders.

    Specs:
  • Premium aluminum alloy canister body
  • Genuine carbon fiber composite end cap
  • Rapid Tuning System (RTS) allows for swapable end cap inserts (sold seperately)
  • Compatible with FMF and OEM headers
  • Resonance Chamber Technology (RCT) lowers sound and refines exhaust gas pressure
  • Increases performance throughout the rpm range
  • Efficient design centralizes mass and makes silencer body less prone to damage in a crash
  • Increased packing material volume in main body canister
  • Meets AMA and FIM sound regulations and requirements
  • Quiet Core 94db end cap insert included
  • USFS spark arrestor included and pre-installed in silencer
  • 100% American made in California
  • Easily removable end cap for quick servicing and repacking
  • Available in various finishes and end cap materials

FMF Factory-4.1 RCT Aluminum Silencer with Carbon End Cap Reviews

Each review submitted enters you into a
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4.7 / 5.0
33 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
25
7
1
0
0
Value
4.7 / 5
Durability
4.8 / 5
Ease of Installation
4.9 / 5
Fitment
4.8 / 5
Performance
4.9 / 5
Finish
4.8 / 5
Features
4.9 / 5
Recommend it?
Yes (21)
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Awesome pipe!!
I put this on my 2018 WR450F along with the competition ECU kit and it is like a whole new bike. Not sure how much the exhaust plays into that but it sounds awesome.
She can breathe
She can breathe
February 5, 2018
Sacramento , CA, US
Purchased
1 month ago
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Great exhaust for the price.
Love it sounds awesome gain power all through low to high range super easy install affordable great quality
2017 ktm 500 exc-f
2017 ktm 500 exc-f
January 30, 2018
Sonora , CA, US
Age: 25-44
Purchased
2 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'4 - 5'6
Value
4 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Great!
Great fit and sounds amazing! Smoothed up the midpower

-m-2014 KAWASAKI KX250F--
User submitted image
User submitted image
January 16, 2018
Clinton , MS, US
Age: 25-44
Purchased
1 month ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
6'1 - 6'3
Value
4 / 5
Durability
5 / 5
Ease of Installation
4 / 5
Fitment
4 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Great Slip-On
Great Slip-on exhaust option, very nice looking and quality, only thing I dont like about the newer FMF systems is the RCT system they use for switching out spark arrestor/quite core, seems to fight you for someone like me who switches from track to trail often id prefer a screw. But overall fantastic exhaust and good performance increase.

-m-2013 KAWASAKI KX450F--
January 11, 2018
Waterford , MI, US
Age: 25-44
Purchased
10 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
6'1 - 6'3
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
I love my FMF exhaust system and I wouldn't get it from anywhere else other than rocky mountain because of the timely delivery
Looks and sounds great and was a breeze to install no better exhaust system out there
December 19, 2017
Las Vegas , NV, US
Age: 25-44
Purchased
2 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Great silencer
I would highly recommend this for anyone wanting to broaden the power output of their machine. Noticeable increase throughout the RPM range and very good improvement to the top end. Runs clean in technical trails, no need to remap. It seems to run smoother and it decreased flame-outs. The fit was perfect, about a 5 min install time. Looks very nice also.

-m-2017 YAMAHA YZ450FX--
November 28, 2017
Oklahoma City, OK, US
Age: 25-44
Purchased
3 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
I just bought rhe fmf rct 4.1 slip on for my 2012 crf450r and love it . Didnt have to get it remapped but had to run it with the spark arrester in it to make it run better without it its way to loud and ran like crap without the remap.
October 24, 2017
Latrobe, PA, US
Age: 25-44
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
FMF always awesome!!
I loved the first one I had so much I had to buy a new one when mine got damaged! Great brand and product!

-m-2012 KTM 350 XC-F--
September 21, 2017
Tampa, FL, US
Purchased
5 months ago
Gender:
Male
Value
5 / 5
Durability
4 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Extremely happy with the product, Cheers.
Super easy installation and quick postage to Australia. Very very happy with it and the tune it puts out.

-m-2017 KTM 450 EXC-F--
September 1, 2017
Newcastle, Nsw , AU
Age: 25-44
Purchased
6 months ago
Gender:
Male
Weight:
221 - 250 lbs.
Height:
5'10 - 6'0
Value
4 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
4 / 5
Features
5 / 5
Recommend it?
Yes
FMF 4.1 alum/carbon slip on .. 2017 Yamaha YZ250FX
Pretty straightforward.. Take off your old exhaust by removing muffler clamp.. spray the header end of muffler where it slides off with wd-40 gently twist off.. remove clamp..clean the end of head pipe with contact cleaner because you don't use the clamp.. you use a high temp silicon to seal it.
Put a small bead of high temp rtv silicon around head pipe. I used permatex copper. Slide FMF on.. put bolts in finger tight.. make sure it doesn't bind.. tighten lower bolt first then upper.. wipe of excess silicon from around head pipe. LET THE SILICON DRY.
The FMF slip on is not threaded for the mounting bolts. It have fasteners that slide on similar to car fender fasteners. They work but don't overtighten them.
The muffler gave me a noticeable difference down low in the power especially coming out of the turns.
But it's sounds so good it could be psychological. Lol
Not real loud .. just beefy
no regrets buying it.. awesome

The spark arrestor isn't installed from the factory.. I'll put it in when I need it for state riding areas..very easy to change it up.
I gave it 4 on finish because the decal was crooked with bubbles in it.. COME ON FMF

-m-2017 YAMAHA YZ250FX--
User submitted image
User submitted image
User submitted image
User submitted image
June 17, 2017
Bourbonnais, IL, US
Age: 45-64
Purchased
8 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Height:
5'10 - 6'0
Each question or answer submitted enters you into a:
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 6 questions Browse 6 questions and 29 answers
Is the sticker on the exhaust blue like in the video?
Kalvyn M on Oct 10, 2016
BEST ANSWER: Stickers are as shown and color is accurate. I bought the aluminum can with carbon tip. Removed the sticker because it didn't look good on a new KTM 500. Buy the pipe, good value, no regrets.
USFS approved?
Joe P on Jul 12, 2017
BEST ANSWER: Yes the one I got came with a usfs approved spark arrestor insert and a sticker to put on the pipe to verify that it is legal .
Would I have to rejet my 12' yz250f for the 4.1 Aluminum with carbon end cap?? (Slip-on only)
Diego Z on Apr 3, 2017
BEST ANSWER: Yes I had to on my wr450 . It picked up a low end bog. Rejeting totally eliminated it. Recommend trying it first and rejet if needed.
The notes indicate the spark arrestor comes pre-installed but appears to actually be part of the quiet insert. Which is true?
Jaron B on Sep 13, 2017
BEST ANSWER: My system was shipped with the spark arrestor separate, it just slid in and was held in with a spring clip that threaded into the end cap
Will this fit a 2005 ktm 450 sxf?
Neal H on Jan 10, 2018
BEST ANSWER: I would doubt it because the frame would require a different location for the mounting tab..You need to call FMF
Will this fit a 2004 crf450r?
Sam H on Apr 22, 2017
BEST ANSWER: To see if this part will fit your machine please enter the make, model, and year into our "Choose a vehicle" drop down boxes found above the product image. If your machine is not listed, we may not carry the right item for your application. If you have a 2017 year model but don't see your machine as an option, please contact a tech via Live Chat or call us at 1-800-336-5437 for assistance.
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