Can Anyone ID my Exhaust Pipes?

[ken_from_hawaii]

Hi all, thank you for reading. My apologies if this is in the wrong section. I have this set of chambers that came with a 77 RD400, but didn't mount correctly and wouldn't fit. I reached out to Gary Shumake at Spec II, who said that they are old RZ350 pipes, but didn't clarify if they were his, or what years they might fit. Any ideas what I got here? I'm planning to sell but haven't the foggiest idea what bike they belong to. Thank you for any help, link to some photos: https://imgur.com/gallery/AzZYH6j

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[kpke]

My best guess is they are Spec2 pipes. Of all of pipes I have had his are the only ones that uses washers welded on to the header pipes for the springs. And the rear mounts and welding (what I can see of it) look like his.

[ken_from_hawaii]

Thank you kpke! Gary just got back to me and confirmed they're SPEC II. "Yes, those are about 1984 SPEC II super silenced RZ expansion chambers. A blast from the past. I think that was the last year of the internal stinger which made them quieter than normal."

Anyone have an idea of what they're worth? Looking to sell in the for sale section or ebay. Thank you!