Hmm... I have a 2021 Rebel 1100, and I as far as I remember I had similar gasket (riser) at the end of the pipe. But I was able to remove it quite easily. Behind the gasket there is a "collar" which is welded in place and painted black. You can see it on your photo.
Moreover you can check the video of QuasiMotard:

about removing the OEM exhaust.
Maybe it is stuck due to the heat of pipes?

 

You’re lucky that your gasket came off with the exhaust. I just tried taking out my Exhaust the gasket is stuck on the header now I don’t have a way to take it off. If you have any suggestion, please let me know.

 

I had a little trouble lining up hangers on the rear but, after loosening up the mid-pipe I wedged the handle of my hammer it was soft rubber and wiggled it until I could slip the bolt in easily worked out fine for installing the Vance and Hines slip on very happy with the results.

 

the exhaust gasket indicated by red arrow can be removed fairly easily

the collar indicated by blue arrow is welded on

remove the gasket

any slip on listed to fit the 1100 should "slip" on

 

I am having the same issue right now I was just wondering how would I takeoff the gasket from the header?

 

As a newbie biker, thank you so much everyone for the help. I'm quite slow it seems.

 

I just installed the Coffman shorty and, yes, that gasket was a bitch to get off but not welded on. I had to use a small chisel and pliers to remove it in pieces. You do need to get down to the bare metal and end with a smooth surface because the Coffman is a tight fit to slip on.

 

I am having the same issue right now. Do you have any suggestion on taking off the gasket from the header??

 

I bought a Coffman’s Exhaust. I have the same issue where the gasket is stuck on the header.

 

Hassan Is Driving...you responded to 2 of Jaygeemo's posts...one with a like and the one below...did you actually read what he said?

If you are not familiar with choosing and using tools for a particular job take your bike to a shop.

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