FMF Fatty Pipe - 2-Stroke

FMF Fatty Pipe - 2-Stroke
FMF Fatty Pipe - 2-Stroke

$173.77 - $341.99
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Description See Also: 87 Reviews 81 Questions Fitment
Item #FMF001X

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87 Reviews
4.8 out of 5 stars
5 Star   79 4 Star   13 3 Star   0 2 Star   1 1 Star   1
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All Reviews
Buster Verified Purchaser
Indy
Durability 4/5 Ease of Installation 4/5 Performance 5/5 Power 4/5 Style 5/5
Satisfied

( 99 cr250 ).
YOU MUST RE-JET both MAIN (178) and PILOT (42) jets and check your needle clip position (2nd) after installing this pipe. FMF has a convenient drop down menu for application selection.. If you do not rejet you will flood your motor out trying to start it AND you'll run WAAAAY too rich. I went from SST to the FATTY. Low end torque is PHENOMINAL!! felt like i was on a 4 stroke while crawling thru the woods. i kept going lower and lower on RPMs in the woods, it would not flame out on me, WOW! You will lose some of the top end, not for drag racing. HOWEVER, I am still tinkering with my jetting, I'm using stock silencer with fatty pipe.

FMF Fatty Pipe - 2-Stroke
FMF Fatty Pipe - 2-Stroke
Mullin Verified Purchaser
Staten Island, NY, USA
Durability 4/5 Ease of Installation 5/5 Performance 4/5 Power 4/5 Style 5/5
Great Pipe !

The FMF Fatty pipe instantly adds easy bolt on power to your 2 stroke !
Great overall performing pipe ... builds plenty of power through the entire rmp range ... best from low through midrange.. perfect pipe for amateur through pro !

HelicopterMechanic Verified Purchaser
Batesville, AR 72501, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Bad a** pipe

Pipe improved power band in all regimes. Smoothed it out and broadened it some.

Motochick713 Verified Purchaser
Grand Rapids, MI
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Fmf is the best

Great fit, fantastic performance

FMF Fatty Pipe - 2-Stroke
MotoEnthusiast
Sacramento, CA, USA
Durability 5/5 Ease of Installation 4/5 Performance 5/5 Power 5/5 Style 5/5
Excellent pipe

Best pipe I have ever purchased. It widened the powerband on my 1999 yz-125 and gave it a slight overall performance increase. If your bike doesn't run after installing the pipe, you will have to change the jetting. Thanks Motosport!

Saferider33 Verified Purchaser
Vallecitos De Los Indios, New Mexico 87025, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Performance Improver!

Easy install. Great look on bike. Improved performance noticeably.

Reaper Verified Purchaser
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Very happy

Great product, fast shipping, perfect fit

Abe95 Verified Purchaser
Durability 5/5 Ease of Installation 1/5 Performance 4/5 Power 5/5 Style 5/5
Greatly built

I have a 97 kx250, I ordered the right pipe but did not mock up to brackets on bike, but I would highly recommend getting pipe.

simonmx33 Top 250 Contributor
Lake Wylie, SC, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
AMAZING PIPE!!

ive had this pipe for a while now, and ill tell you, this thing rocks! ive been in multiple bad crashes and not a ding on the pipe, it deffinitely freed up some power both mid and top rpm. the sound is remarkable. of course my bike is tuned and may sound different than any 125sx, but i guess itll give you a taste of how crisp it sounds, paired with the shorty, it sounds good. and ill include an attachment of the sound,

Iguanajoes Verified Purchaser
St Johns, FL 32259, USA
Durability 3/5 Ease of Installation 4/5 Performance 4/5 Power 4/5 Style 5/5
Second time is a charm

I was very pleased with the last fatty but had to replace when I found hairline cracks from wear over time. This one was a slightly different shape but fit after adjusting rubber mounts.

Sounds great, runs strong. I would suggest paying close attention to the bend in the pipe behind the front wheel. Keep it clean and dry to avoid premature failure.

MOTONIKO11
Panama
Durability 5/5 Ease of Installation 4/5 Performance 5/5 Power 5/5 Style 3/5
ATC250R 1986

THE BEST IN THE MARKET,HAVE 20 YEARS AND LOOKS LIKE A NEW ONE.

mike Verified Purchaser
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Its like a new bike!

Best pipe on the market with most overall power gain and great top end power. Its like a new bike!

FMF Fatty Pipe - 2-Stroke
Dteracing Verified Purchaser
Nixa, MO 65714, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great pipe

Great pipe love were the power kicks in much wider range than my old gnarly

ktmrider
Durability 4/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
GREAT HEADER

I recommend this header to anyone and everyone this is overall the best header around although it is kind of easy to dent but besides that I give it 5 stars

Mallett Verified Purchaser
Pismo
Durability 5/5 Ease of Installation 3/5 Performance 5/5 Power 5/5 Style 4/5
FMF Fatty - 2013 KTM 150XC

Took a few tries on jetting, had to lean up PJ, go to richer Needle and MJ.
Final jetting = 40 PJ, NOZH Needle and 178 MJ. Better bottom, much better mid and even better top end and over-rev.

Liked it so much on the 150XC, bought one for the 150SX as well. The 150 XC/SX is a great motor made even better, more usable and forgiving on tight technical or aggressive track riding.

2013 150XC w/ Fatty and Turbine Core
wishihadone
Durability 4/5 Ease of Installation 5/5 Performance 4/5 Power 3/5 Style 3/5
Wish everything was this easy

The pipe was an excellent fit and went on with ease, no tweaking or adjustment needed. Engine does seem to breath a little better now. I got no real complaints about the pipe but it would be nice if it was available in black, just seems to be a shame to scratch up such a nice finish. I still need to do a little fine tuning with the carb but it seems to perform as advertised. No complaints here. I cant say anything about durability yet as it hasn't served as the impact point,,,, yet.....(fingers crossed..) but I did invest in an aluminum pipe guard to help protect the investment.

FMF Fatty Pipe - 2-Stroke
kdubb Verified Purchaser
New York, NY, USA
Durability 2/5 Ease of Installation 4/5 Performance 4/5 Power 4/5 Style 5/5
Great Pipe and sounds amazing.

put this pipe on my cr125 sounded great and gave it more power but i crash my bike on the side where the pipe is located and it had a bit of a dent. But this pipe shines like no other.

none Verified Purchaser
Pennsylvania, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Chris

I have seven bikes ,two have Gnarly pipes, one has has SST,the rest have Fattys,FMF makes the best pipes

mikesean Top 25 Contributor
Durability 4/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Best 125 pipe out there!!!

Instant power gains and sounds amazing in the high revs, just buy it you wont regret it.

Kelly Verified Purchaser
Brentwood, CA
Durability 5/5 Ease of Installation 4/5 Performance 5/5 Power 5/5 Style 5/5
Fatty Pipe

Works great, looks great!

See 20 More Reviews
81 Questions
Answered:   78
Not Yet:   3
pash
Location: India
Q: Hi would this fit a Yamaha RXZ135 2stroker?
12 days ago
Cooper03
Location: Dover, AR 72837, USA
Q: I have a cr85r?
2 months 24 days ago
I want a new fatty pipe I'm thinking of a fmf because ive been hearing good thangs about them I read about the fatty pipe and idk know what it means by better throttle respons is it quicker because I want a fmf pipe that will give me more power threw the power band with my original one once I hit the powerband all my power is gone I want to know if I keep giving it power will it keep going and keep getting faster or will it just do the same thang just rev up
Kyler
Location: Eagle County, CO, USA
Q: How many cubic inches is it?
2 months 29 days ago
How many cubic inches is it compared to a gnarly pipe that would fit a 2002 yz125
Moto177
Q: I have a FMF SST pipe is the FMF Fatty a upgrade or no?
Over 6 months ago
Hames686
Over 6 months ago
A: The fatty has more mid to top end range, I have one on my cr250 and it's great. I've heard the sst restricts the flow. But it's all preference.
Moto177
Q: I have a fmf sst pipe is pipe a upgrade, I am looking for fast throttle performance?
Over 6 months ago
MotoSportExpert
Expert MotoSport Staff
Over 6 months ago
A: The FMF Fatty Pipe offers more tractable power, improved throttle control. Provides power gains throughout entire power band.
Rich
Location: Tulsa
Q: Will it rust?
Over 7 months ago
In other words. How long will it stay shinny
MotoSportExpert
MotoSport Staff Expert
Over 7 months ago
A: No this FMF Fatty Pipe will not rust. It is nickel-plated for maximum durability.
The "works", or raw (bare metal) finish pipes will rust and take much more work to keep clean and looking fresh than the nickel plated pipes do.
Craigmack
Location: Bend, OR, USA
Q: Will this unit fit the 1991 LT250R Quadracer?
Over 7 months ago
MotoSportExpert
Expert MotoSport Staff
Over 6 months ago
A: Yes, Just be sure to correctly select the Year/Make/Model of your ATV before ordering so we can be sure to send you the correct pipe for your ATV. Also, feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
logan
Location: Flint, MI, USA
Q: Can i use this with a pro circuit r-304 shorty?
Over 8 months ago
MotoSportExpert
MotoSport Staff Expert
Over 8 months ago
A: Yes you should have no issues.
logan
Location: Flint, MI, USA
Q: Is this a left side pipe for a 2000 kx80?
Over 8 months ago
my kx80 pipe is on the left side and in the picture it looks like its on the rights side will this pipe be on the left side when i order it.
MotoSportExpert
Expert MotoSport Staff
Over 8 months ago
A: Yes, it would mount that same as your stock pipe. The image is a generic image supplied by the manufacturer for reference only. It may not be displaying the exact pipe for your bike. Just be sure to correctly select the Year/Make/Model of your bike before ordering so we can be sure to send you the correct pipe for your bike. Also, feel free to give us a call at 888-676-8853 and we would be happy to help you out with your order.
Danb19
Location: Blackwood nj
Q: Does this come with springs?
Over 9 months ago
MotoSportExpert
MotoSport Staff Expert
Over 9 months ago
A: No the FMF pipes do not come with springs.
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