FMF Fatty Pipe - 2-Stroke

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

$197.99 - $341.99
10% Off - Save up to $38.00

Select your bike to see if this exhaust fits
Description See Also: 86 Reviews 80 Questions Fitment
Item #FMF001X

Read More
86 Reviews
4.8 out of 5 stars
5 Star   79 4 Star   12 3 Star   0 2 Star   1 1 Star   1
Write a Review

Write your review and you'll automatically be entered in our monthly drawing. Include an image or video to DOUBLE your chances to win!

Write Your Review Write a review to win $500
All Reviews
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!

DirtSnowRider
Chico, CA, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great Product

Helped broaden the power band and bring the extra power I needed

Dakota2Kedik Verified Purchaser
South Bend, IN, USA
Durability 5/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great Bolt on HorsePower..

Great bolt on horsepower for the 2012 ktm 125 took the lowend bog away that most 125s have..Made the throttle responce alot better without rejetting or changing anything but the pipe... add the shorty silencer and WOW..WHAT A DIFFERANCE....

Great Bolt on horsePower!!!!!!!
Dirtschmobn Top 250 Contributor
South Bay, CA
Durability 4/5 Ease of Installation 5/5 Performance 5/5 Power 5/5 Style 5/5
Great pipe

installed on a 2000 YZ125
First off, this pipe makes the power band much broader! I am very happy with this addition. I also added the Vforce3 reed block at the same time, so I would say these are two complementary add ons. I used the jetting specs that came with the pipe and I'm loving the broadened power band and crisp throttle response. I already had an FMF turbine core silencer, so I just repacked it before installing the pipe.
The install was very easy, and the pipe comes with orings already installed. I purchased the oring kit with springs just in case, but only used the springs so my old ones could be retired.

I was however, un happy with how the pipe arrived. There were some stains on the outside (pictured) that I would hope an expensive part like this would be free of before shipping. I cleaned most of it off, but signs still remained. I noted that the durability is not high because the pipe is larger than stock, and an expansion chamber is very vulnerable anyway, and can be beat up easier. Due to the larger pipe size, I also moved the kick starter back a few teeth to maintain clearance.

one of the stains
See 20 More Reviews
80 Questions
Answered:   78
Not Yet:   2
Cooper03
Location: Dover, AR 72837, USA
Q: I have a cr85r?
1 day 8 hours 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?
6 days 10 hours 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?
3 months 18 days ago
Hames686
3 months 17 days 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?
3 months 19 days ago
MotoSportExpert
MotoSport Staff Expert
3 months 18 days 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?
4 months 10 days ago
In other words. How long will it stay shinny
MotoSportExpert
Expert MotoSport Staff
4 months 9 days 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?
4 months 26 days ago
MotoSportExpert
MotoSport Staff Expert
3 months 29 days 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 6 months ago
MotoSportExpert
Expert MotoSport Staff
Over 6 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 6 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
MotoSport Staff Expert
Over 6 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 6 months ago
MotoSportExpert
Expert MotoSport Staff
Over 6 months ago
A: No the FMF pipes do not come with springs.
TKS100
Q: If I am currently running an SST pipe on my 02 cr125, would I have to change the jetting if I get the Fatty pipe?
Over 8 months ago
MotoSportExpert
MotoSport Staff Expert
Over 8 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. If your bike is running good with your current jetting and SST pipe you will likely not need to rejet.
1-10 of 80
Fitment
See all bikes that this part fits...
See Fitments