125-200cc 2012-2013 FMF FATTY DIFFERENCES

Hello All !! I am hoping someone can answer this. FMF list different part numbers between 2012-2013 Fatty for the WR125. Has anyone had one of each of these side by side to see the differences. I have contacted FMF and they have stated that are different by didn't state what had changed. They also listed different part numbers for the mufflers as well.

Yeah, was told the same thing too when i called FMF. The sales guy wouldn't go into specifics. I ended up ordering p/n 025163 and the TC2.

I'm having trouble finding a US dealer selling the 13 one online. The Australian distributor is hopeless in getting stuff in. I would really love to know what has been changed as I have just ordered the 144 kit.

I bought my Fatty and TurbineCore2 (for 2013 WR125) directly from FMF. The online stores I talked to could not tell me much about the differences between model years of the Fatty. FMF seemed "guarded" about the differences, but I went ahead and bought the '13 pipe.

I'll try to take some measurements of the expansion chamber section of my Fatty and OEM pipe. I'll post the data under this thread. I'm curious how they differ.

EDIT: 2013 OEM pipe vs. FMF Fatty

UPDATE: Below are the measurements of my FMF Fatty (#025163). Measurements were made at 2 inch intervals, beginning from the silencer end. I used a waxed thread to measure, then compared the measured length to a tailor's tape. Treat measurements as APPROXIMATES. It was a PIA trying to keep the thread 90degrees to the chamber's axis.

9.8 cm @ Silencer end along Right edge of weld bead
17.2 cm @ 2 inches (")
24.5 cm @ 4"
29.8 cm @ 6"
33.8 cm @ 8"
36.4 cm @ 10"
36.3 cm @ 12"
35.0 cm @ 14"
32.2 cm @ 16"
30.6 cm @ Header end along Left edge of weld bead.

I have no idea what the inside dimensions are at my measuring points. The Black Art of 2-stroke expansion chamber is too much for me to grasp. I hope the numbers help. At least you have a reference point now. Hopefully others will chime in.

I didn't measure my OEM pipe. It's 110 F in my garage, and I wussied out.

UPDATE 2: OEM Pipe - installed

10.0 cm @ Silencer end along Right edge of weld bead
17.8 cm @ 2 inches (")
25.2 cm @ 4"
30.4 cm @ 6"
34.2 cm @ 8"
36.5 cm @ 10"
36.5 cm @ 12"
36.0 cm @ 14"
32.6 cm @ 16"
(Not measured) @ Header end along Left edge of weld bead.

Header section - OEM (Fatty)
[not measured a the 18, 20, & 22 inch locations because mounting bracket]

21.2 cm (20.6) @ 24"
18.8 cm (18.6) @ 26"
17.0 cm (17.0) @ 28"
16.0 cm (15.7) @ 30"
15.0 cm (14.9) @ 32"
14.2 cm (14.2) @ 34"

Visually, the OEM vs Fatty seem very close. Dimension wise there are some differences, but seam/weld bead heights did influence my measurements (as well as my caveman method). The overall length of the Fatty is 45-1/4" . I'll measure the OEM when I install the Fatty.

My conclusion after this drill: The FMF Fatty sure looks purrty!

Hi 72 racerx,

I bought a new FMF Fatty from the states for our 2010 model and I haven't fitted as yet it says husqvarna WR 125 10 / WR 150 11 F pipe part # 025145
not sure what if any changes from 2010 to 2013. you are quite welcome to view compare ??

When you order make sure you get the orings or reuse your old as they come bare.

Orings didn't come with the Fatty (part #025163) I bought direct from FMF. Maybe orings are supplied with the pre-2013 pipes.

Thanks for the info guys !!! I have ordered a full Husky/Pro Circuit system through Halls as they were going cheap and also due to an emailed response from FMF on another couple of questions I had for them. I was less that happy with their response on one question.

I will see how the PC system goes with the 125 barrel then the 144 kit I have sitting here waiting to be installed. I will probably get a FMF system sometime in the near future to experiment with.

I did ask FMF if the later 13 exhaust will work with the 144 kit and they couldn't tell me as they hadn't tried it.

Well I hope your Pro Circuit system is better fitting than mine. I got it because of the same discount deal but I'm wondering if something changed on the subframe mount for the silencer between '12 and '13 because on my '13 CR 125, the silencer to pipe engagement is subpar----where the two come together there is only about 1/4 of overlap. I've considered welding another mounting tab on the silencer to get it farther forward or adding an inch of pipe to the silencer to get a much better mounting point to the pipe.

Quite disappointing for a pipe bearing an Husqvarna badge.

IIRC, the PC silencer only works with the PC pipe.

Thanks for the heads up Venturini ! Husky and PC list it as fitting the 13 models. Maybe there has been some changes that most of us are not aware of. I also find it strange that no parts book listings are available for the 13 CR/WR 125 as of yet (If someone can post a link if it is would be much appreciated). Maybe FMF are right and there are changes with the 13 model. I just wish they would say what the changes were.

You are correct on the PC silencer only works with the chamber.

Well my Husky/Pro Circuit exhaust arrived today and has already been fitted. I didn't experience any fitment issues that Venturini has. There was probably about a quarter inch of the overlap that wasn't covered. The stock rubber sleeve that covers the same joint on the OEM exhaust is a bit of a hit and miss fit though. It came with a new exhaust oring and a pair of springs which was nice.

Another interesting point to be noted that my stock muffler will fit on the PC chamber contra to what PC's website states.

I will endeavour to post some photos of the weekend.

Any chance you still have the box the pipe came in? I'm wondering if the dealer ordered a pipe for a '12 instead of a 13 for me----my stock silencer was 1/2 shorter than the PC silencer I got. The part number on the pipe box I got was # 8539212.

Sorry I no longer have the box. According to Husqvarna 12 & 13 are the same part number. If I recall the number was the same as yours. I was supplied with a Type 296 silencer. The Aust spec bikes are supplied with a different stock silencer than the USA market bikes.

Is this the problem you were having with the joint.

Yes, that is the problem spot----my total stinger length is 8 3/4 inch to the weld at the silencer and the length of the tip is 1 inch from the end to the angled stop (the stop for the rubber sleeve). If I had as much overlap as you got I'd be more than happy. These measurements are for the 296 silencer I got.

Oh well, for the price of the bike I can just live with it until I get the '13 FMF pipe to replace the PC pipe that got smashed and cracked at the first race because nobody makes a carbon fiber guard that remotely fits it----not really that surprised---used to it when dealing with a brand whose right hand doesn't know what the left hand is doing and half the time the right hand doesn't even know that there is a left hand to begin with.

just found this thread as i ordered a FMF Fatty for a 2010 WR 125 which fits perfect to my 2013 Model.

I have a pc silencer on my 2013 cr 125 fitted to the standard pipe ok