Great fit, fantastic performance
FMF Fatty Pipe - 2-Stroke
- 84 Reviews
- 78 Questions
With well over 35 years of racing experience behind it, the Fatty pipe delivers race-proven performance. The Fatty broadens and smoothes out the power curve while boosting gains throughout the entire power band, more low-end, more mid, and increased over-rev. No matter what type of riding you do, the Fatty has the benefits you're looking for.
- More tractable power, improved throttle control.
- Provides power gains throughout entire power band.
- Carbon steel with a nickel-plated finish for maximum durability.
- FMF Racing's Tru-Flo stamping process ensures a perfect fit and optimum performance.
- Can be used with FMF or stock silencer.
- FMF's most popular 2-stroke pipe.
- Note: Pipe may include factory indentations for proper installation clearance.
Note: For closed course competition use ONLY. Not intended for street use.
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!
Easy install. Great look on bike. Improved performance noticeably.
Great product, fast shipping, perfect fit
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.
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,
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.
THE BEST IN THE MARKET,HAVE 20 YEARS AND LOOKS LIKE A NEW ONE.
Best pipe on the market with most overall power gain and great top end power. Its like a new bike!
Great pipe love were the power kicks in much wider range than my old gnarly
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
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.
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.
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.
I have seven bikes ,two have Gnarly pipes, one has has SST,the rest have Fattys,FMF makes the best pipes
Instant power gains and sounds amazing in the high revs, just buy it you wont regret it.
Works great, looks great!
Helped broaden the power band and bring the extra power I needed
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....
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.
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.