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Discussion Starter · #1 ·
My 1980 CX500C has good pipes and the muffler shell looks good, too, but the baffles are rusted out. My bike only has 10k, so I'd really like to gut the mufflers, kill the rust and install new baffles. I have read on this forum about the Harley mufflers, rejetting, the very nice 2-1 systems without the H-pipe, along with the pros/cons of the H-pipe. I would like to keep my bike exhaust stock for as long as possible. If a baffle isn't available, has anyone had any luck at fabricating one? I have access to a machine shop, so I can work up a pretty good part.
 

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I had a problem with my baffles rusting out at the back ring (one came out while riding, boy what a wake up call that was lol). Since my mufflers were rusted outside and the chrome in pretty rough shape, I put Dyna ones off a harley softail on mine.



Now, if your back ring inside the muffler is still ok, you could fab something up. The ones on mine had 3 rivets holding in the baffles, and if they are gone or removed the "innards" come right out. I will run out and see if I still have the innards and get a pic. I may have considered fixing mine if the ring in the back was ok, but mine was toast (by ring I mean a metal lip inside the rear of the muffler that acts as a mounting plate)



Hope that help, and once I get a pic you will see what i mean
 

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Here is what the guts look like



[media]http://i1237.photobucket.com/albums/ff467/stern-69/DSCF5591.jpg[/media]

[media]http://i1237.photobucket.com/albums/ff467/stern-69/DSCF5590.jpg[/media]





Hope that helps
 

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Discussion Starter · #4 ·
Thanks for the pictures, FADM. That cup shape is what is rusted out on mine. I don't think these baffles will stay in much longer, and I am not sure about the lip/ring. What about removing the old baffle, taking off the muffler, inserting a baffle into the header pipe (they are readily available) and then remounting the empty muffler? My biggest concerns are correct back pressure, quiet operation and looks.
 

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Those perforated baffles are the resonators, and should be in the muffler can. I doubt any help would come by putting them in the headers. Probably more troubles really. These exhaust systems are pretty tightly designed to the engine. Yes other mods have worked fine, with other tweaks to carb jetting and the like, but with your bike looking as nice and stock as it is, perhaps fabricating something like what FADM showed would be beneficial.



Joel in the Couve
 

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Well, first off, the lip that cup rivets to it pretty thick, think mine failed because the PO probably tried to cut them out and gave up.



From what I can see of the whole baffle, once you get it out you may find only the cup is rusted bad, as the tube seems to be really think. May be able to get away with just making a new cup piece and using the existing tube. Would make the job a lot easier.
 

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Discussion Starter · #7 ·
Well, first off, the lip that cup rivets to it pretty thick, think mine failed because the PO probably tried to cut them out and gave up.



From what I can see of the whole baffle, once you get it out you may find only the cup is rusted bad, as the tube seems to be really think. May be able to get away with just making a new cup piece and using the existing tube. Would make the job a lot easier.


Here are some pictures of my baffles:



Right Baffle



Left Baffle



So by drilling out the rivets, the whole baffle should slide out of the end of the muffler?
 

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Yes. It takes a bit to pull them out, as one was a real pain. The end of the tube i believe fits ito another section inside the muffler. I had to tap and pull a bit, but once loose it slides right out. When I got mine off, 3/4 of the inner ring on one (all on the other) had been cut through by what looks like a torch of some sort (even had a hole through the muffler that looked like it was melted).



I did push one back in to see if I could get it back in (was contemplating making a new ring to mount it to) and it went in fine. Before I started trying to fix it I scored a set of Dynas of a Harlet softback and decided to go that route (as the chrome on my mufflers was rusted and pitted bad)
 

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Discussion Starter · #9 ·
Yes. It takes a bit to pull them out, as one was a real pain. The end of the tube i believe fits ito another section inside the muffler. I had to tap and pull a bit, but once loose it slides right out. When I got mine off, 3/4 of the inner ring on one (all on the other) had been cut through by what looks like a torch of some sort (even had a hole through the muffler that looked like it was melted).



I did push one back in to see if I could get it back in (was contemplating making a new ring to mount it to) and it went in fine. Before I started trying to fix it I scored a set of Dynas of a Harlet softback and decided to go that route (as the chrome on my mufflers was rusted and pitted bad)


Did you dismount the muffler from the header?
 

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That's sad those rear plates are so rusted out. That could indicate some internal problems considering the external condition of the bike. However, I think you should be able to do something to fix it if you have the means. Yes, if the inside baffles are still okay, it might be done. Here is a diagram that floats around here, and appears to be from Honda for the general system. From FADM's pics, it seems a bit different, but I think the concept is there. You indicated you might have access to the tools needed to rig something up. Be a shame to see those nice chrome shells go to waste.







Here are mine, and the little spot at the bottom is just moisture from the wash down. I have many more miles on my 82 C, but always covered or garaged. *Oh, it's for sale if you need another
*







This side was prior to a wash, and before a plug change, I was burning a bit rich. It is fine like the left one.







Joel in the Couve
 

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Discussion Starter · #11 ·
That's sad those rear plates are so rusted out. That could indicate some internal problems considering the external condition of the bike. However, I think you should be able to do something to fix it if you have the means. Yes, if the inside baffles are still okay, it might be done. Here is a diagram that floats around here, and appears to be from Honda for the general system. From FADM's pics, it seems a bit different, but I think the concept is there. You indicated you might have access to the tools needed to rig something up. Be a shame to see those nice chrome shells go to waste.


I will certainly try to save the shells before going aftermarket. I hope that nothing is wrong internally - I can smell coolant when the bike is running, so I have some type of leak, hopefully not the water jacket. Does coolant circulate in the heads on these bikes, or just along the cylinder walls?







Here are mine, and the little spot at the bottom is just moisture from the wash down. I have many more miles on my 82 C, but always covered or garaged. *Oh, it's for sale if you need another
*


Haha - You never know! Are you interested in vintage audio gear? You have a very clean looking ride - I covet thine mufflers.
 

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Actually, when I took my baffles out the pipes were still on the bike. When I rebiult the bike I was not able to seperate any of the exhaust part, and since I didnt want damage any of it I didnt try to "Conan" them apart. Once I got the baffles freed up (drilled out the one rivet that was the only thing holding one, other fell out while riding) I used a pair of pliers to grab the cup side (or what was left of it) twist a bit and pull the whole thing out. When I replaced the mufflers I had to use a pipe wrench (4' one) to "spin" the pipes to break them free from the 30 year seal, then they came out (I did totally trash the pipes, one even twisted like a pretzil, but since I wasnt reusing the it didnt matter)



You should be able to do this without taking anything off the bike, that way there is no way you can accidentaly damage the pipes. May take a little time and patience, and a soaking of WD40 or similar sprayed inside with a straw sure cant hurt
 
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