I acquired a stock exhaust system off an '82 1100, on the understanding that it should fit on the '83.
After attempting to install it today, I learned that while the right-side pipe fits well, the left-side pipe runs into the lower mounting lug for the left-side shock on the rear swingarm and can't be lifted up into place to be bolted on.
I'm unsure whether this is an issue with the '82 exhaust being a different geometry, or if it's an issue with the swingarm itself.

I know that a PO replaced the front end (wheel, forks, and triple tree) with parts off a '96 Katana. The front wheel is a cast 3-spoke hub painted white, and the rear wheel matches which I assume means it's off the same katana. The guy didn't mention anything about the rear swingarm being replaced, but I suspect it may also be off the katana, which may be why i'm having problems fitting the stock exhaust.

Can anyone identify whether this is a stock GS swingarm or not?​

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