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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

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Our Price: $359.99$494.99

MSRP: $399.99 - $549.99 - You save up to $55.00 (10% off)

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FMF Factory 4.1 RCT Sound Bite

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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

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4.8 / 5.0
57 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
45
11
1
0
0
Value
4.6 / 5
Durability
4.8 / 5
Ease of Installation
4.8 / 5
Fitment
4.8 / 5
Performance
4.9 / 5
Finish
4.8 / 5
Features
4.8 / 5
Recommend it?
Yes (45)
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
Highly recommend fmf 4.1
I received it before the date was given love the pipe great perches for the bike

-m-2016 HUSQVARNA FC 250--
April 6, 2020
Spelter , WV, US
Age: 25-44
Purchased
2 weeks ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Durability
5 / 5
Ease of Installation
4 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
4 / 5
Features
5 / 5
Recommend it?
Yes
Great performance and sound with or without spark Arrester
Really like the look this puts on my bike. I wish I mounted it it the right spot I ended up scraping it with my tire just had to move it over. Fits great to stock header. Don’t have to use adhesive if u don’t have any it just prevents small leaks. My 560 degree F. adhesive melted away over time
User submitted image
User submitted image
User submitted image
March 7, 2020
Burbank, WA, US
Age: 15-24
Purchased
1 month ago
Gender:
Male
Weight:
161 - 190 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
Bad A*s
Love the look, the sound and the price. Using it for the first time at our local OHV park, then turn around and withing 1 minute or less have the sparky removed and get some roost time on closed course MX track. Nice all around sound pipe. Way to go FMF!

-m-2017 KAWASAKI KX250F--
February 28, 2020
Tracy, CA, US
Age: 15-24
Purchased
2 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Value
4 / 5
Durability
4 / 5
Ease of Installation
3 / 5
Fitment
4 / 5
Performance
4 / 5
Finish
4 / 5
Features
4 / 5
Recommend it?
Yes
Looks trick, but expensive
Bought to make sure I have a true USFS spark arrestor for trail riding. Pipe looks and sounds great, quality is great. It is a bit expensive compared to other slip on options.

I docked ease of installation due to the spark arrestor insert. I was able to get it in, removing may be a bit difficult if I ever decide to do so. Even if I don't, my past Pro Circuit pipe on a different bike was much easier to install & remove the spark arrestor. Overall still happy with the purchase.

-m-2019 KTM 350 XC-F--
February 21, 2020
Spokane Valley, WA, US
Age: 25-44
Purchased
1 month 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
Sounds amazing
Looks great and sounds great! If your looking for power probably should get the full system! Definitely is lighter as well!
February 3, 2020
Reno, NV, US
Age: 15-24
Purchased
9 months ago
Gender:
Male
Weight:
161 - 190 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
4 / 5
Recommend it?
Yes
Quality all around!
This pipe is a quality piece all around. The fit and finish of it is great and it sounds awesome too. I was skeptical because of the price but you get what you pay for.....i would recommend this to anyone looking for an all around quality upgrade to their bike.

-m-2012 YAMAHA YZ450F--
February 3, 2020
MAYVILLE, WI, US
Age: 25-44
Purchased
3 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
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
5 months 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
1 year ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Show more
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Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 17 questions Browse 17 questions and 61 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 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.
are these exhaust systems designed to be rubber mounted on the sub frame for the 2019 kx450? i was told that if they are not rubber mounted like the stock muffler it could cause the sub frame to fail?? anyone have any info on this? Thanks
jonathon t on Jan 27, 2020
BEST ANSWER: I added this exhaust to my KTM 2018 350 EXC-F. When I swapped out the exhaust I used the stock rubber mounting grommets on the FMF exhaust. Cheers!
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: The pipe is designed to not run with a clamp, though you can use the stock clamp if needed
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.
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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