FMF Factory-4.1 Silencer With SS Mid-Pipe

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FMF Factory-4.1 Silencer With SS Mid-Pipe
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FMF Factory-4.1 Silencer With SS Mid-Pipe

Our Price: $343.99$382.49

MSRP: $399.99 - $424.99 - You save up to $56.00 (14% off)

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Additional Videos

FMF Factory | Inside Look

How To - Repack A Silencer For Your ATV Or Motorcycle

FMF Factory 4.1 RCT Sound Bite

RM YouTube Channel

Details

    FMF’s Factory 4.1 Silencer with Stainless Steel Mid Pipe is one of the best choices you can make when you want to keep your motorcycle or ATV running at peak performance. With the 4.1 you can expect to get a universal bump in performance that reaches across the entire rpm range. You’ll also get a hi-flo end cap that lets you tune the 4.1’s power with optional rev tubes and spark arrestors. The 4.1 isn’t just raw power though. FMF also prizes value and durability. It shows in the 4.1’s solid construction from excellent base materials and a precisely designed canister shape that maximizes internal packing volume to lower exhaust noise and extend service periods.

    Specs:
  • Tunable, spark arrestable silencer for your 4 stroke
  • Stamped with AMA approval for sound requirements
  • Aluminum canister body with stainless steel end cap and mid pipe
  • Easy bolt-on installation
  • Angle cut canister moves mass closer to center of machine
  • Hi-flo end cap accepts modular tuning inserts or spark arrestor
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

FMF Factory-4.1 Silencer With SS Mid-Pipe Reviews

Each review submitted enters you into a
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
 
4.7 / 5.0
29 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
24
4
0
0
1
Value
5.0 / 5
Durability
5.0 / 5
Ease of Installation
5.0 / 5
Fitment
5.0 / 5
Performance
5.0 / 5
Finish
5.0 / 5
Features
5.0 / 5
Recommend it?
Yes (2)
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
Would recommend to anyone perfect fitment easy to install and very fast shipping to Australia. Very happy!
User submitted image
Added Jan 29, 2018
January 29, 2018
Sydney, 2763, AU
Age: 25-44
Purchased
8 months ago
Gender:
Male
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
Best investment i have ever made
I put this exhaust on my YFZ and it made the bike sound insanely better gave it a good performance boost and the looks and sound are awesome perks. I would recommend this exhaust to everyone.
September 1, 2016
Plain City, UT, US
Age: 15-24
Purchased
over 3 years ago
Gender:
Male
Weight:
131 - 160 lbs.
Height:
5'10 - 6'0
OMG!!! Hold on!
Got the FMF Factory 4.1 and the FMF EFI programmer. Still have the stock header pipe. Air box still standard with a Twin Air. Can't wait to get this to the track. Like the other guy says, it's a rocket ship.

Installation was easy, programmer very user friendly. The first 3 stock settings are 1, 1, 1. I ended up setting mine for now at .5, 2.5, 1.5. Will probably go up if I change the air box. Overall, love it!

Machine this part was bought for: 2010 YAMAHA YFZ450
July 23, 2016
FL
Awesome!
Nothing works better, can't go wrong with this. Beast mode!!

Machine this part was bought for: 2005 HONDA CRF450
July 12, 2016
UT
great product
Well built, sounds great. spark arrestor was included which i wasn't sure of. love the tuning insert ability.

Machine this part was bought for: 2006 HONDA CRF450R
July 17, 2015
CA
wow
Easy install, great sound, no problems

Machine this part was bought for: 2005 HONDA CRF450R
March 12, 2015
SD
Low end torque!!!!
This thing is horse power in a box. A must have for hole shots!

Great fit, high quality. It's loud, but in a good way!

Machine this part was bought for: 2005 HONDA CRF450X
February 18, 2015
TX
fmf 4.1
what can I say about fmf. they are the top exhaust company for a reason. awesome sound and great performance gain and best price on rocky mountain. its a no brainer

Machine this part was bought for: 2008 KAWASAKI KFX 450R
May 12, 2014
CA
WOW
this product is a great buy, bought it for my kx450 06, gave me more power, sounds crazy, and looks sick.. for the price I highly suggest to purchase the powerbomb header aswelll, i believe its going for 179.00, I am very happy with this product, except how FMF didnt supply me with a little bit of high heat silicone to seal the mid-pipe to the header, but besides that this is a great buy. full system your looking at 500-550.

Machine this part was bought for: 2006 KAWASAKI KX450F
June 22, 2013
ON
super Awesome Product
Awesome Product

Machine this part was bought for: 2010 POLARIS OUTLAW 525 S
December 12, 2012
CA
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 1 question Browse 1 question and 1 answer
will this fit with the stock head pipe?
Nolan N on Jun 28, 2017
BEST ANSWER: yup,, it would fit with the stock pipe,, it did on my bike (2008 Polaris outlaw 525s)
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