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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
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FMF Factory-4.1 RCT Aluminum Silencer with Carbon End Cap

Our Price: $314.99$494.99

MSRP: $349.99 - $549.99 - You save up to $55.00 (10% off)

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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
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

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

Each review submitted enters you into a
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
 
4.8 / 5.0
51 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
40
10
1
0
0
Value
4.6 / 5
Durability
4.8 / 5
Ease of Installation
4.9 / 5
Fitment
4.8 / 5
Performance
4.9 / 5
Finish
4.9 / 5
Features
4.8 / 5
Recommend it?
Yes (39)
Value
4 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
4 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
fmf
fitment was perfect, sounds great pretty much got it for the spark arrester.
November 19, 2019
puyallup, WA, US
Age: 25-44
Purchased
1 month ago
Gender:
Male
Value
3 / 5
Durability
4 / 5
Ease of Installation
4 / 5
Fitment
4 / 5
Performance
5 / 5
Finish
5 / 5
Features
4 / 5
Recommend it?
Yes
Great sparky but...
Awesome product but pretty spendy. There are so few options for a silencer/sparky and this one is the best option for performance with price aside. My son loves the way it looks and sounds so that’s a plus........

-m-2019 YAMAHA YZ250F--
June 26, 2019
Selah , WA, US
Age: 25-44
Purchased
over 2 years ago
Gender:
Male
Weight:
221 - 250 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
Perfect!
Went on alot easier than the stock silencer that's for sure. Even the clamp from Yamaha tightened down on this silencer. Sound is awesome & performance went UP! I needed a spark arrester but I ended up with more than that! Thanks Rockymtn! YZ 450 FX perfect product, would recommend.

-m-2017 YAMAHA YZ450FX--
February 22, 2019
Washington, UT, US
Age: 45-64
Gender:
Male
Weight:
221 - 250 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
Gotta love it!
I love the FMF pipes. It has that low deep brapp sound which is what I was looking for, and trust me it’s loud. Loud enough for me to put the silencer in it to keep the neighbors somewhat happy.

-m-2019 HUSQVARNA FE 501--
January 11, 2019
Port Charlotte, FL, US
Age: 25-44
Purchased
10 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Value
4 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
4 / 5
Features
4 / 5
Recommend it?
Yes
Excellent pipe
Really opened up the bike, easy install and completes the desmog. Not too much louder over stock fe501 exhaust
January 4, 2019
Ellensburg , WA, US
Age: 45-64
Purchased
1 year ago
Gender:
Male
Weight:
221 - 250 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
FINALLY!!!!!!
Ordered this on april 14th with another company. Never got it from them. Was looking on RMATVMC and they had it so I ordered it from them. Got it in today and put it on. Looks awesome! My sticker was blue instead of red. The muffler came with the quiet insert and clip i installed, a wash plug, replacement bolt for midpipe and 8 fmf stickers. Needs to be runed but am very happy with sound and look

-m-2011 HONDA CRF450R--
November 19, 2018
Winston, OR, US
Age: 25-44
Purchased
1 year ago
Gender:
Male
Height:
6'1 - 6'3
Value
4 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
4 / 5
Recommend it?
Yes
Great slip on.
Absolutely great exhaust. Bought it for my yz450f and it took care of the raspy noise and replaced it with a deep loud tone. Being more open than the stock exhaust it even added a little bit of power.

-m-2018 YAMAHA YZ450F--
User submitted image
Added Oct 17, 2018
October 17, 2018
Princeton , WV, US
Age: 15-24
Purchased
1 year ago
Gender:
Male
Weight:
131 - 160 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
Happy
Fits great, sounds great, and feels like it improves mid-range also. I’m loving it!!

-m-2015 KTM 250 SX-F Factory Edition--
Great fit and sounds awesome!! Feel like it helps with mid-range also
Great fit and sounds awesome!! Feel like it helps with mid-range also
August 10, 2018
Princeton, KY, US
Age: 15-24
Purchased
1 year ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'4 - 5'6
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
Overall good.
Sounds deeper from low to mid but then goes back to a similiar sound to stock from mid to top. Personally would have loved a deeper sound the whole way through. Also dissapointed like others that such an expensive exhaust has no clamps and cant use the stock one. Didnt notive any performance difference and didnt expect to but has a nice sound and is not to loud so its good for trail riding and not making every one around you angry about noise.

-m-2016 YAMAHA YZ450FX--
User submitted image
Added Aug 9, 2018
August 9, 2018
Fort mcmurray, AB, CA
Purchased
1 year 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
The best $400+ ive ever spent. Definitely WOKE my bike up!
This is the first aftermarket pipe ive ever bought and im totally impressed with the overall power increase. It really woke up my yz250fx all through the power band especially the top end! Overrev for daysand a spark arrestor! Beautiful fit and finish, and simple installation. A little deeper sound then stock but not any louder.
User submitted image
Added Jul 9, 2018
July 9, 2018
Nampa , ID, US
Age: 25-44
Purchased
1 year ago
Gender:
Male
Weight:
221 - 250 lbs.
Height:
6'1 - 6'3
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 16 questions Browse 16 questions and 58 answers
does it come with bolts to install?
A shopper on May 27, 2019
BEST ANSWER: The only bolts are the ones mounting it to the frame and you use your stock ones you should not need any it comes with the springs to attach pipe
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.
Do I really need this for my 250f?
A shopper on Jan 12, 2019
BEST ANSWER: The FMF silencer with carbon end cap is worth every penny. It's lighter than stock, looks better and really opens up the mid-range of the motor. Shopping for one at RM is as easy as it comes.
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: When I purchased mine the spark arrestor was not installed already and I had to install it myself, was pretty easy to do.
Will this affect the engine mapping on a fuel injected bike? 2018 Ktm. Asking because I see that people have had to rejet their carbs. Thanks
Christopher M on Jan 12, 2019
BEST ANSWER: I installed this on my 16 YZ250f and didn’t change the mapping at all, and it runs awesome. Didn’t really notice any super big performance gains, runs a little crisper and the sound is way better, a lot deeper sounding. The stock exhaust was really raspy sounding.
Is there any difference in the Horse power delivery of the anodized 4.1 fmf and the aluminum 4.1 fmf?
Taylor S on Mar 31, 2019
BEST ANSWER: No. The anodizing process is coloring applied to the outside surface of the aluminum.
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
What size pipe would I need for my ktm sxf 250 2019 ?
nigel a on Jul 27, 2019
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 2020 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.
My exhaust did not come with a flange clamp and my stock one does not clamp down enough to tighten. Does anyone know the diameter of the slip on pipe section? I have a 2015 YZ250f but I am out of state and trying to order!

Thanks!
Charles M on Jun 18, 2019
BEST ANSWER: A clamp is not needed
Can anyone tell me the stick head pipe inlet size on a 2009 KTM EXC-R 450? Please
A shopper on Feb 17, 2019
BEST ANSWER: We do not have the stock header in-stock and we do not have access to this imformation. we do have stock headers available to order.
Will this fit a 2007 ktm 250 sxf?
A shopper on Jul 27, 2018
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 2018 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.
I bought a 2012 RMZ250 a few months back. I am just getting around to putting on this FMF pipe that the guy gave me with the bike. When I tried to put it on, the end of this pipe did not fit on the header of the stock pipe. I looked at the stock pipe and it looks like he has some sort of bushing inside of it to make it fit snug. Is there some sort of bushing I can get for this pipe to fit the stock header correctly? I tried to use the clamp that is on it, but the clamp does not clamp tight enough to make it a snug fit. Thanks!
Monte S on Jul 19, 2018
BEST ANSWER: I purchased for a 2017 ktm 500, it came with a reducer to fit the stock head pipe. Will need to source the reducer
Will this ship to Australia?
A shopper on Jun 11, 2018
BEST ANSWER: Yes, it will. Please email [email protected] with a list of part numbers you'd like to order and your full shipping address and they will be able to reply with a shipping quote for you.
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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