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exhaust question K6

LackLuster

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Hi,
absolutely new here, but not to CB750's or motorcycles.

I am extremely lucky and i wont hide that fact.
I had a '75 CB among other bikes back when i as young as i am old enough that they were common back then. 30+ years ago, but that is for the introduction thread.

I found a 1976 Cb 750K for $2700 last summer with 22k on the odo that had been "restored" by a BMW enthusiast. The bike was 80+% . Still needs front and rear fenders in chrome (he painted the front and the rear... it is just not correct and the tail light is not correct).
The exhaust is a 4 to 2 and works fine... BUT... most everything else is correct and the bike is absolutely solid. It starts after a few (4-5) kicks or on the electric starter within 30 seconds... if it isn't January first.

so here is the problem and the question.
today i found a set of 341 stamped exhausts. Not knowing the stamps were there, I bought them for $50 from craigslist on the long chance they might fit and not be a set of 550 pipes. They are not rusted out and have a lot of chain lube/oil residue caked on the insides. there are a couple of intended flat spots and a couple of minor dents on the bottom side. But as i started working on them, they are coming clean and looking great. They still have the correct muffler protector/heat shields.
They are all stamped HMCB750 (L1/R1/L2/R2) HM341
Yes this looks too good to be true.

Is it too good to be true? Have i found a set of original K2-K6 mufflers or do Replicas have stamps as well to be 'authentic'?

I have seen what a set of original mufflers can go for. I hoped that i would find something more authentic at a low price, and it looks like i may have. But if they are really original, i am obviously thinking about the money and also sending it along to someone who wants to restore.

I have a 68 427 convertible Corvette and the burden of "originality" is something i understand. But i didn't buy the bike with that in mind. So i may part with a once-in-a-lifetime find to support a restoration, or mount them up if they are just replicas.
thanks for looking at his.
i did search for exhaust stamps and anything else i could think of that might answer the questions without a post.
i can get some pics of the stamps if that makes a difference.
 

dirtdigger

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341's are correct for your K6. Although not posted, there are different 341 from the factory, 341 started in 72 and as they went up in years they changed the internal baffling. The reproduction aftermarket pipes are also stamped HM341 so there is a possibility they are reproduction. Kind of hard to tell unless you have a know factory set to compare them to.
 

LackLuster

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thanks for the reply.
Since my bike is K6 anyway it would be the last of these type of exhaust. I assume they would be the most restrictive anyway. Is that correct? If so, anything older would flow more freely, so really nothing to lose.
I am adding pics here in case someone has a set they can compare to.
You can see the difference between the state they were in when i got them and how well they cleaning up after about an hour. They are not perfect by a long shot. I have some polishing to do once they are finally clean.

picone.jpg

picthree.jpg

picfour.jpg

picfive.jpg

A couple of these pictures show off the stamps pretty well. hopefully someone can say with some certainty that they are Repros or no.
Any additional information would be good to know.
No matter what the outcome, im happy i found them in a craigslist ad with a bunch of chopped up Harley mufflers.
 

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