FMF 4.1 Muffler insert?

I have the full FMF 4.1 system on my 08 YZ450F. I noticed there is an insert in the end of the muffler. It looks to only be held in by an allen key. Is there anything to gain by removing it?

I have the full FMF 4.1 system on my 08 YZ450F. I noticed there is an insert in the end of the muffler. It looks to only be held in by an allen key. Is there anything to gain by removing it?

Not really, just added noise. You can buy different sized rings that fit in the end, as well as a spark arrestor or quiet core, or you can run it with nothing. I have tried two different sized rings, no ring, and a quiet core and performance wise I like the ring that comes with it, though they really didn't make much of a difference.

so I should just leave it alone..

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