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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4.8 / 5.0
40 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
31
8
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
4.8 / 5
Features
4.8 / 5
Recommend it?
Yes (28)
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
Love it!
This thing is a beauty! Added power through out.

-m-2018 KTM 350 EXC-F--
April 13, 2018
Walnut Creek, CA, US
Age: 25-44
Purchased
2 months ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
6'1 - 6'3
Value
4 / 5
Durability
4 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Sounds good, comes with spark arrestor
I bought this to have a spark arrestor so I can ride public land. It works great and is an easy install. Make sure you buy some high temp silicone to properly install.
April 11, 2018
Raleigh, NC, US
Purchased
3 weeks ago
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
4 / 5
Performance
4 / 5
Finish
4 / 5
Features
3 / 5
Recommend it?
Yes
2016 KX450F
Pipe is pretty good for a slip on! I got this pipe for the spark arrestor to rip some local trails when i get tired of motos at the track. Picked the FMF 4.1 over the pro circuit t6 due to the look.

I’ve never been a fan of aftermarket pipes, due to the price and the fact that 450s really don’t need more power...

But now I see why people get them! The bike had more over rev and was a lot easier to ride. A little more down low allowing me to go a gear higher in corners with no clutch.

The bike did not need a tune, (still using stock air filter) but I can see where a tune would be beneficial. It seems to not pull as hard when pinned, but just barley. You only notice it if you really really think about it. Expected anytime you addd more air flow to a motor. I guess that’s what the full system and a tune is for.

One complaint is the way the spark arrestor is secured. FMF uses a ring that you have to jam into the inside of the pipe. And then pry out in order to take it out. A little hard and annoying to do. At that price for the pipe, I’d expect a little more ease of use. Exhaust note is about the same as stock KX450F, just louder.
User submitted image
Added Apr 5, 2018
April 5, 2018
Santa Clarita, 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
Stepson loved this on his 17 KTM 450sxf
My stepson is a motocrosser, but needed a pipe so he could ride some trails with us. He rides a 17 KTM 450sxf and loved this pipe. He said it opened up the bike more than stock, even with the spark arrestor.
March 26, 2018
Phoenix, AZ, US
Age: 25-44
Purchased
2 months ago
Gender:
Female
Weight:
101 - 130 lbs.
Height:
5'4 - 5'6
Value
4 / 5
Durability
4 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Love the pipe easy to install
Easy fit sounds awesome looks great 2017 kX 250f...........
User submitted image
Added Mar 12, 2018
March 12, 2018
Talent , OR, US
Age: 25-44
Purchased
1 month ago
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'10 - 6'0
Value
5 / 5
Durability
5 / 5
Ease of Installation
5 / 5
Fitment
4 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
OH YEAH!!!
Bolt on power! Easy to install, well written directions to help you install if needed. Came with a dozen FMF stickers and spark arrestor. The finish on this pipe is a thing of beauty. My bike hits harder and on the bottom, and pulls harder. It added a nice grunt to the bike. FMF makes a great product, no doubt about it.

-m-2015 KAWASAKI KX250F--
User submitted image
User submitted image
March 11, 2018
LA, CA, US
Age: 25-44
Purchased
1 month 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
4 / 5
Finish
5 / 5
Features
4 / 5
Recommend it?
Yes
Factory 4.1
Awesome fit and finish as always from FMF. Rocky mountain came through with the quick shipping! Always a pleasure shopping with them.

-m-2017 YAMAHA YZ250F--
Slip on
Slip on
February 26, 2018
Clifton Springs, NY, US
Age: 25-44
Purchased
2 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
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
3 months 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
5 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
3 months ago
Gender:
Male
Weight:
191 - 220 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 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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