Please help identify exhaust system

I have a 2000 WR400 that I bought used with an aftermarket exhaust system. I can't figure out which manufacturer made it.


The headpipe, midpipe, and muffler look aftermarket. The muffler is tack welded onto the midpipe and there are provisions for springs at each union. The muffler is extremely loud (sounds like a straight pipe). 


I'm trying to add a spark arrestor to the endcap of my muffler. Can anyone help me identify who made any of these parts?



Note: I tried to get forest legal by changing to a White Brothers slip on exhaust system (with spark arrestor) that I bought used from someone with a WR426. When I tried mount the white brothers system, my aftermarket headpipe was too short, and I was left with a gap. All the joints between the headpipe, midpipe, and muffler are located at different points when compared to a stock setup.


5 Pictures Attached:

#1 shows the two slip on systems. White brothers is on the top. Custom aftermarket system is on the bottom. Mounting points are lined up.

#2 shows the unknown aftermarket headpipe

#3 shows the tack welded muffler to the unknown aftermarket midpipe

#4 shows muffler end cap removed

#5 shows the gap that results when trying to mount a WR426F white brothers slip on to the unknown aftermarket head pipe






Edited by lr103

Looks like an early FMF to me, both pipe and silencer.

I agree, it looks real close to one of my FMF's although my end cap is pop riveted on where this one looks to have a three screws holding that aft end cap on.


 I have a Big Gun on another bike that looks real close to having a similar end cap on it. I removed that end cap, cut out a piece of stainless screen to make it spark arresting, as well as made a little thin aluminum disc with smaller holes in it and it quieted down the pipe real nice as well as gave me a little more back pressure which gives you more torque and less high end which is good for climbing hills.

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