FMF Factory Fatty Pipe

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FMF Factory Fatty Pipe
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FMF Factory Fatty Pipe

Our Price: $215.99$233.99

MSRP: $239.99 - $259.99 - You save up to $26.00 (10% off)

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Additional Videos

FMF Factory | Inside Look

FMF Factory Fatty Pipe Sound Bite W/ Q-Stealth

How to - 2 Stroke Pipe Install

RM YouTube Channel

Details

    The FMF Factory Fatty Pipe is a 2 stroke exhaust header that takes cues from the works pipes of yesteryear, smoothing out power in a lightweight construction that pays tribute to the racers of old.

    With the Fatty Pipe expect a smooth power band devoid of spikes but with better power throughout the rev range. More low, more mid, and increased over-rev. Great for most types of riding where you want more control of your power band.

    A bare finish that shows the heat-affected weld areas is attractive and true old school. The construction is also full of old school quality with lightweight 20 gauge steel for the body and thicker 19 gauge for the header portion. And of course it has the same hand welded, hand pounded seams to increase flow..

    Specs:
  • Better power in low and mid ranges
  • Higher over-rev
  • Smooth power curve
  • Lightweight 20 gauge steel body
  • Tougher 19 gauge steel header
  • Most models include new O-rings
  • Hand welded and pounded seams
  • Made 100% in the USA
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

FMF Factory Fatty Pipe Reviews

Each review submitted enters you into a
$100 gift card monthly drawing and a
$500 gift card quarterly drawing!
 
4.9 / 5.0
33 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
29
3
1
0
0
Value
4.8 / 5
Durability
4.6 / 5
Ease of Installation
5.0 / 5
Fitment
5.0 / 5
Performance
4.9 / 5
Finish
5.0 / 5
Features
4.9 / 5
Recommend it?
Yes (28)
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
Smokers
Always have run a FMF on all my bikes and sons also. Hold up great (should run some kind of guard on all pipes) but do hold up w/o. Definitely noticed broad increases on power band!
August 16, 2018
Coatesville , PA, US
Age: 45-64
Purchased
1 year 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
Have 3
Takes a bit of work to keep it nice but what doesn’t.

-m-DIRT BIKE--
August 3, 2018
E falmouth, MA, US
Age: 25-44
Purchased
3 months ago
Gender:
Male
Value
5 / 5
Durability
4 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
I needed it
65 pipes are pricey but aT least it's a good quality fmf
July 19, 2018
Stafford, CT, US
Age: 25-44
Purchased
7 months ago
Gender:
Male
Weight:
<100 lbs.
Value
5 / 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 Fatty!
I recently purchased this header pipe to replace my stock one, my first impressions were fantastic. Pipe looks amazing, increased mid range in my power band, and the fitting was spot on. FMF has always proven to be successful with their products and this pipe doesn't fall short of expectations. Thanks to RM for excellent service and a speedy delivery.

-m-2015 YAMAHA YZ250--
June 28, 2018
American Falls, ID, US
Age: 25-44
Purchased
3 months ago
Gender:
Male
Weight:
191 - 220 lbs.
Value
4 / 5
Durability
3 / 5
Ease of Installation
5 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Nothing looks better
Noticed a nice little boost across the board over stock on both my 150sx and 250XC .Nothing looks better than a colored up raw finish pipe. I use Maxima SC1 after a wash to keep the rust away, makes keeping them looking good easy.

-m-2018 KTM 150 SX--
June 3, 2018
panama city, FL, US
Age: 25-44
Gender:
Male
Weight:
161 - 190 lbs.
Height:
5'7 - 5'9
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
Looks Factory!
I kept debating on the factory finish vs the nickel plated fatty pipe. I am so glad I went with the factory raw finish, it looks amazing! Just keep it oiled well with wd-40 and some scotch brite pads to keep it looking new with no rust.

-m-2017 HUSQVARNA TX 300--
User submitted image
Added Apr 9, 2018
April 9, 2018
Charleston, WV, US
Age: 25-44
Purchased
6 months ago
Gender:
Male
Value
5 / 5
Durability
5 / 5
Ease of Installation
4 / 5
Fitment
5 / 5
Performance
5 / 5
Finish
5 / 5
Features
5 / 5
Recommend it?
Yes
Best 2 stroke pipe on the market
The quality and finish on these are awesome. My son rides a KTM 85SX and this just completes his bike. He can notice the difference in power and loves having a stronger mid to top end. Do yourself and your hands a favour and buy some decent spring pullers though.
February 21, 2018
Greenwith, South Australia, AU
Age: 25-44
Purchased
11 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
Grey pipe
Really smoothed out the power on my 300. Glad I bought the fatty for this particular bike
February 2, 2018
Lubbock, TX, US
Age: 25-44
Purchased
9 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
Well worth the money
This pipe and silencer made i huge difference in the perfomance of my 300 KTM , never had a pipe make so much of a change to a motorcycle ever. it performd just like they basid it would . i would highly recomend this to anyone who rides a 300 KTM.

-m-2015 KTM 300 XC-W (E-Start)--
January 26, 2018
Puyallup, WA, US
Age: 45-64
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
5 / 5
Recommend it?
Yes
LOVE
Looks super cool and adds a lot to the bike! Love love love it

-m-2017 KTM 300 XC--
December 14, 2017
Reeds spring, MO, US
Age: 15-24
Purchased
10 months ago
Gender:
Male
Weight:
251 - 280 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 8 questions Browse 8 questions and 25 answers
what is the difference between fmf fatty big bore and fmf fatty?
Dylan F on Aug 19, 2016
BEST ANSWER: The exhaust port size on the big bore will be larger. The big bore is to change the 85 into a 105cc, or supermini.
Will this fit on a 2003 Yz250 with an FMF Fatty pipe installed?
Daniel D on Mar 5, 2017
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BEST ANSWER: Have a 2002 with a factory fatty. And it fit with,no issues.
What jetting is used with this pipe on a ktm 300 or do I need to change from stock?
A shopper on Dec 24, 2017
BEST ANSWER: I would invest in the lectron and forget about it. We have ran the mukini and keihin on our race bikes and the lectron out performs both without the hassle of worrying about the weather and elevation.
Part# 1046500034 - Cool pipe - does this pipe any type of coating to keep from rusting?
Terry K on Sep 26, 2017
BEST ANSWER: It has a thin oil spray from the factory to keep it from rusting while sitting in inventory , but once rode and washed this is gone. After every wash give it a spray with wd40 and clean with a steel whool pad and it willlook brand new every ride
Will I need to change the jetting on my 250 ktm 2017?
christopher G on Aug 26, 2018
BEST ANSWER: I purchased the Fatty Pipe for my 2017 TE300 last year when I purchased my bike and I did not have to change the jetting. I've had many rides on it without any issues. It's a nice pipe. Perfect fit.
Is it necessary to do silencer with the pipe or is it OK to get a pipe and use the Stocks silencer?
Tyler M on Feb 9, 2018
BEST ANSWER: I did both pipe and silencer not sure how it works with out silencer
Will I have to get a different size jetting with this pipe for my KTM 2018 sx85?
Joe B on Sep 26, 2018
BEST ANSWER: Well you could depends where you live and have crisp you want the bike to run
Can i get this fmf pipe fore rm 250 2008?
A shopper on May 8, 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.
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