Author Topic: Serial Number on Exhaust  (Read 861 times)

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Offline daddydane750

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Serial Number on Exhaust
« on: March 29, 2008, 09:40:03 PM »
Since I finished my carburetors, I've started working on some other parts of the bike. I found out my '78K frame has a '71 engine (with it's '78 carbs). I noticed that my pipes weren't showing up on photos of other '78s I saw on the internet. So my next quest is to find who my exhaust originally belong to. I've got photos below. The serial number in the close-up photo is HMCB750 SR HM341. The other three pipes have LR, SL, and LL in place of SR (each one referring to the pipe's position I guess). I haven't found anything that has a reference guide to the numbers on the pipes. Who did Frankenstein get his exhaust from?


D. Dane Williams
1978 CB750K
1978 CB750K
1992 Nighthawk (may she rest in peace)

Offline 754

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Re: Serial Number on Exhaust
« Reply #1 on: March 29, 2008, 09:49:44 PM »
They are 71 or 72 through to 76 CB 75o exhaust.
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Offline Jonesy

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Re: Serial Number on Exhaust
« Reply #2 on: March 30, 2008, 04:59:52 AM »
The '77 and '78 Cb750 K models had rolled steel megaphone mufflers, rather than the split-half construction style of the earlier exhausts, which you have. The pipes for your bike were only made for 2 years, and are practically unobtainium new, unlike the "HM341" pipes.
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