Topic: O-Ring Chain Damage on CB550

[rusty_tank]

Hiya folks. I'm currently doing a tear down and rebuild on my 1978 Honda CB550. While cleaning behind my sprocket cover I found the plug/o_ring to the left of the countershaft (output sprocket seal) was worn down, see pic. It's clear the chain had worn on the the case and the plug itself. Because I've had a small leak from behind the sprocket cover for some time I've been sourcing info on the different o-rings. While searching for info on the output sprocket seal I found the following threads regarding the plug to the left, http://forums.sohc4.net/index.php?topic=75149.0, and, http://forums.sohc4.net/index.php/topic,1526.0.html. I'd bet this is where my leak is coming from. Seeing as these threads are from several years ago I thought I'd revisit the topic/post a new thread for those who don't know about it. So in short here's the deal, if you have a CB550 don't use an o-ring chain. It'll #$%* up your cases. I'm planing on applying some JB Weld to seal it and I've already ordered the appropriate chain. I'll try and post pics of the process or at least a finished product pic.

[DaveBarbier]

I had the same damage on mine but luckily it didn't leak. When I split the cases I replaced the old seal with OEM. It was SO thin and close to leaking!

[flybox1]

Yes, its well documented here about the thicker chains doing this type of damage.
IIWY, id clean it up with de-greaser, acetone, and a slice of emory paper to slightly scuff the lip of the case there around the lip of the seal.
Then id paint on some permatex(black) non-hardening sealer. 
JB weld would be a ibtch to have to clean off later on if you ever split the cases (to do it right).

[strynboen]

i use a o ring thain..have a small marking....you can use a lathe to give a bit more Space on the back side..take a few milineters of the f spoke ??(zahnrad), at front side ..then it mover aut..and frees up the backside

[rusty_tank]

Yes, its well documented here about the thicker chains doing this type of damage.
IIWY, id clean it up with de-greaser, acetone, and a slice of emory paper to slightly scuff the lip of the case there around the lip of the seal.
Then id paint on some permatex(black) non-hardening sealer. 
JB weld would be a ibtch to have to clean off later on if you ever split the cases (to do it right).

Well flybox you make a good point about the JB Weld being a ibtch to remove, but I don't think I'll be splitting the cases for quite some time...although who knows. But I guess that's not your point right? It's about whenever that time comes it'll be one more thing to deal with. I'm contemplating your suggestion for sure. Thank you brotha.

[rusty_tank]

i use a o ring thain..have a small marking....you can use a lathe to give a bit more Space on the back side..take a few milineters of the f spoke ??(zahnrad), at front side ..then it mover aut..and frees up the backside

That's an interesting idea! Thanks for the suggestion strynboen