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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: $359.99$404.99

MSRP: $399.99 - $449.99 - You save up to $45.00 (10% off)

View Product DetailsSee all machines the FMF Factory-4.1 Silencer With SS Mid-Pipe fits.

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  • "Customer service is priority #1 at Rocky Mountain ATV/MC. We value our customers and strive to be the best shopping experience- when you buy from us, you are buying lifetime service."

    -Dan Thomas, CEO and Founder

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    We take pride in offering no hassle returns. In the event of a return, please call, email or chat with us to receive a solution to the problem. For apparel that doesn't fit quite right, Click here to see our Fit Guaranteed Program.

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    We will stand behind all products we sell with regards to manufacturing defects in workmanship and material. Most products are limited to the manufacturer's warranty. However, we will do everything in our power to take care of the problem.

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    Email:sales@rockymountainatv.com
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    FMF not only focuses on building a hi-performance race silencer, FMF also focuses on low sound levels and value in performance. With the FMF Factory 4.1 silencer with SS Mid-Pipe you will get the quality of performance you are looking for and a great looking setup on you machine. The FMF Factory 4.1 silencer with SS Mid-Pipe is easy to install and will make you ready for the racing season. FMF has 30 years of racing experience behind them making FMF exhaust one of the top leading developers in that USA. FMF Factory 4.1 Silencer with SS Mid-Pipe is also stamped with AMA approval for meeting their sound requirements on most motorcycle models.
  • Features Factory-4.1 Silencer and Stainless Steel Mid-Pipe.
  • Based on the Factory-4.1 full system, the uniquely shaped end cap and angle cut oval canister moves the muffler closer to the center of the bike.
  • Newly designed hi-flo end cap is modular for tuning the power with optional rev tubes or installing a spark arrestor module.

FMF Factory-4.1 Silencer With SS Mid-Pipe Reviews

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1 of 1 people found this review helpful.

WOW

Comments On Jun 22, 2013: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.

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1 of 1 people found this review helpful.

super Awesome Product

Comments On Dec 12, 2012:Awesome Product

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1 of 1 people found this review helpful.

Amazing sound

Comments On Sep 23, 2012:It sounds amazing. it wasnt hard to instal,l very easy fit. It slipped right on, few screws, came with the nessicary spacers to make it fit just right. The sound is great, definity a good buy. Added power, will definity continue buying FMF parts. Thanks Rocky mountain ATV!

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1 of 1 people found this review helpful.

Loud!

Comments On May 30, 2012:Nice pipe, nice sound. Very loud but never ticketed or questioned.

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0 of 0 people found this review helpful.

Great set up

Comments On Apr 24, 2012:Super easy to install. Doesn't come with the lube stuff, but I put it on there with out it and it's been working great.

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0 of 0 people found this review helpful.

Added power and great sound

Comments On Mar 19, 2012:Love how easy to install, and sounds awesome!

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2 of 2 people found this review helpful.

Thank you ROCKY MOUNTAIN MC!

Comments On Apr 28, 2011:Ive left all kinds of reviews on here trying to win the gift certificate to rocky mountain atv, Not only did I win, I won the quarterly drawing for $500.00 Gift card!! Super stoked and used it to buy this Exaust and a ti megabomb header for my 2010 crf 450. Excellent Fit and finish, and big gains in bottom and top end pull.... THANK YOU Rocky Mountain MC!!!!

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0 of 0 people found this review helpful.

sweet mid pipe and silencer kit

Comments On Mar 09, 2011:everything fit great improved mid range and top end power.sound is different than most.

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0 of 0 people found this review helpful.

Great power boost with Megabomb, but now too loud

Comments On Aug 31, 2010:Colorado just passed legislation that bikes need to be less than 96 db. I'm not thinking this will pass a sound check on my WR250F with a Megabomb (which should quiet it down about 1.5 db supposedly). The extra power is astounding - it will be very hard to give up this pipe if I have to. Excellent build quality and durability. I don't have a bad thing to say about it, except too loud, which is how FMF designed it and that was fine with me when I bought it in 2007 as there was no noise about sound being an issue and I used to ride in the middle of nowhere, many miles from the nearest person. I may have to trade it for an FMF Q4, or other.

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2 of 2 people found this review helpful.

FMF 4.1 Factory Exhaust - 2008 YZ250F

Comments On Nov 23, 2009:I purchased my FMF 4.1 pipe last week and put it on my bike. I rode at Ocotillo Wells and I felt an increase in power throughout the power band. The throttle is more responsive. Front end comes up quicker and easier. The bike sounds great too. I will be purchasing a power bomb header soon and I will re-jet the bike when I have purchased the new header (felt solid with the stock jetting). Sweet muffler!

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