FMF Fatty Pipe - 2-Stroke

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

$114.77 - $341.99
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Item #FMF001X

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88 Reviews
4.8 out of 5 stars
5 Star   80 4 Star   13 3 Star   0 2 Star   1 1 Star   1
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All Reviews
samz54
Huntersville, NC 28078, USA
Durability 4/5 Ease of Installation 4/5 Performance 5/5 Power 5/5 Style 4/5
Amazing Pipe!

Awesome pipe, installed it pretty easy. Made a huge difference in my power-band (I ride a 96kx125). Glad I bought this.

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.

See 20 More Reviews
84 Questions
Answered:   80
Not Yet:   4
Jdog
Q: Ive read that the mounts from the fatty dont line up excatly on a 1997 kx 250 and info on tha?
Over 5 months ago
Looking to install fatty on it
Ttavis
Q: Wondering if it will fit my bike because when this pipe is hooked up it comes out on the right side but my stock pipe comes out on the left?
Over 5 months ago
jbam19
Top 100 Contributor
4 months 15 days ago
A: Yes it will fit the 1998 kx80, the photo is just representative and not the actual expansion chamber for your bike, it will come set up to whichever side came stock on the bike.
Grunt7
Location: South Carolina, USA
Q: I have a 2017 yz 250 2 stroke,what would be the best jetting or the bike?
Over 5 months ago
MotoSportExpert
MotoSport Staff Expert
Over 5 months ago
A: There is not a specific setting I could give you for jetting your bike. It would really depend on your location (altitude/temperature) and how your bike is running with the current jetting. Jetting can be very tricky, there isn't one setting that will work everywhere with every bike. I would recommend taking your bike to a local motorcycle dealership’s service department to have your bike properly jetted.
Due to the variations that may come into effect when tuning an engine (i.e. pipes, intake, altitude, cams, displacement, standard or high compression pistons, etc.) we CANNOT offer jetting recommendations.
pash
Location: India
Q: Hi would this fit a Yamaha RXZ135 2stroker?
Over 6 months ago
Cooper03
Location: Dover, AR 72837, USA
Q: I have a cr85r?
Over 8 months 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?
Over 8 months 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?
1 year ago
Hames686
1 year 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.
Bucky
Over 6 months ago
A: The SST is for MX and SX. It has superior top end, but kinda sluggish on the lower end. The Fatty is for the woods, very low RPM torque, awesome for crawling around, Almost acts like a 4T.
Moto177
Q: I have a fmf sst pipe is pipe a upgrade, I am looking for fast throttle performance?
1 year ago
MotoSportExpert
Expert MotoSport Staff
1 year 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?
1 year ago
In other words. How long will it stay shinny
MotoSportExpert
MotoSport Staff Expert
1 year 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?
1 year 1 month ago
MotoSportExpert
MotoSport Staff Expert
1 year 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.
1-10 of 84
Fitment
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# Part Numbers
Product Variant Manufacturer Part #
FMF Fatty Pipe - 2-Stroke 020375
FMF Fatty Pipe - 2-Stroke 021036
FMF Fatty Pipe - 2-Stroke 021048
FMF Fatty Pipe - 2-Stroke 021021
FMF Fatty Pipe - 2-Stroke 020378
FMF Fatty Pipe - 2-Stroke 020020
FMF Fatty Pipe - 2-Stroke 021006
FMF Fatty Pipe - 2-Stroke 021040
FMF Fatty Pipe - 2-Stroke 021052
FMF Fatty Pipe - 2-Stroke 021000
FMF Fatty Pipe - 2-Stroke 021031
FMF Fatty Pipe - 2-Stroke 021044
FMF Fatty Pipe - 2-Stroke 023049
FMF Fatty Pipe - 2-Stroke 025073
FMF Fatty Pipe - 2-Stroke 025119
FMF Fatty Pipe - 2-Stroke 025130
FMF Fatty Pipe - 2-Stroke 025003
FMF Fatty Pipe - 2-Stroke 025069
FMF Fatty Pipe - 2-Stroke 025006
FMF Fatty Pipe - 2-Stroke 025060
FMF Fatty Pipe - 2-Stroke 025091
FMF Fatty Pipe - 2-Stroke 025088
FMF Fatty Pipe - 2-Stroke 020050
FMF Fatty Pipe - 2-Stroke 022048
FMF Fatty Pipe - 2-Stroke 022003
FMF Fatty Pipe - 2-Stroke 020054
FMF Fatty Pipe - 2-Stroke 022015
FMF Fatty Pipe - 2-Stroke 022040
FMF Fatty Pipe - 2-Stroke 022052
FMF Fatty Pipe - 2-Stroke 020045
FMF Fatty Pipe - 2-Stroke 022000
FMF Fatty Pipe - 2-Stroke 022060
FMF Fatty Pipe - 2-Stroke 022006
FMF Fatty Pipe - 2-Stroke 022034
FMF Fatty Pipe - 2-Stroke 024023
FMF Fatty Pipe - 2-Stroke 023055
FMF Fatty Pipe - 2-Stroke 020107
FMF Fatty Pipe - 2-Stroke 023006
FMF Fatty Pipe - 2-Stroke 023018
FMF Fatty Pipe - 2-Stroke 023059
FMF Fatty Pipe - 2-Stroke 023000
FMF Fatty Pipe - 2-Stroke 020133
FMF Fatty Pipe - 2-Stroke 024041
FMF Fatty Pipe - 2-Stroke 024049
FMF Fatty Pipe - 2-Stroke 020147
FMF Fatty Pipe - 2-Stroke 024053
FMF Fatty Pipe - 2-Stroke 020149
FMF Fatty Pipe - 2-Stroke 020138
FMF Fatty Pipe - 2-Stroke 024000
FMF Fatty Pipe - 2-Stroke 020006
FMF Fatty Pipe - 2-Stroke 020014
FMF Fatty Pipe - 2-Stroke 020015
FMF Fatty Pipe - 2-Stroke 020017
FMF Fatty Pipe - 2-Stroke 020018
FMF Fatty Pipe - 2-Stroke 020031
FMF Fatty Pipe - 2-Stroke 020048
FMF Fatty Pipe - 2-Stroke 020034
FMF Fatty Pipe - 2-Stroke 022044
FMF Fatty Pipe - 2-Stroke 020037
FMF Fatty Pipe - 2-Stroke 020039
FMF Fatty Pipe - 2-Stroke 020051
FMF Fatty Pipe - 2-Stroke 020042
FMF Fatty Pipe - 2-Stroke 022012
FMF Fatty Pipe - 2-Stroke 020124
FMF Fatty Pipe - 2-Stroke 020127
FMF Fatty Pipe - 2-Stroke 020130
FMF Fatty Pipe - 2-Stroke 020143
FMF Fatty Pipe - 2-Stroke 020142
FMF Fatty Pipe - 2-Stroke 020132
FMF Fatty Pipe - 2-Stroke 020135
FMF Fatty Pipe - 2-Stroke 024034
FMF Fatty Pipe - 2-Stroke 020137
FMF Fatty Pipe - 2-Stroke 020145
FMF Fatty Pipe - 2-Stroke 020150
FMF Fatty Pipe - 2-Stroke 020087
FMF Fatty Pipe - 2-Stroke 023037
FMF Fatty Pipe - 2-Stroke 020088
FMF Fatty Pipe - 2-Stroke 020089
FMF Fatty Pipe - 2-Stroke 020091
FMF Fatty Pipe - 2-Stroke 020092
FMF Fatty Pipe - 2-Stroke 020094
FMF Fatty Pipe - 2-Stroke 020097
FMF Fatty Pipe - 2-Stroke 020104
FMF Fatty Pipe - 2-Stroke 020105
FMF Fatty Pipe - 2-Stroke 020109
FMF Fatty Pipe - 2-Stroke 020390
FMF Fatty Pipe - 2-Stroke 025019
FMF Fatty Pipe - 2-Stroke 020069
FMF Fatty Pipe - 2-Stroke 020075
FMF Fatty Pipe - 2-Stroke 025052
FMF Fatty Pipe - 2-Stroke 025040
FMF Fatty Pipe - 2-Stroke 025018
FMF Fatty Pipe - 2-Stroke 025151
FMF Fatty Pipe - 2-Stroke 021058
FMF Fatty Pipe - 2-Stroke 025092
FMF Fatty Pipe - 2-Stroke 025115
FMF Fatty Pipe - 2-Stroke 025145
FMF Fatty Pipe - 2-Stroke 025150
FMF Fatty Pipe - 2-Stroke 025159
FMF Fatty Pipe - 2-Stroke 025163
FMF Fatty Pipe - 2-Stroke 025182
FMF Fatty Pipe - 2-Stroke 025197
FMF Fatty Pipe - 2-Stroke N/A
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