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To ring or not to ring!

nohandels

New member
Ok I finally got off the right jug. There had been a mouse nest in the cylinder and a dead baby "just bones" 20 years ago? maybe? I got the jug off and there was just surface rust on the inside. Cool! But the first ring is stuck in place on the piston. I have the piston in a bag of blaster. The ring is starting to free up.

My question is: should I replace the rings on both sides since there are readily available? The bike has only 18000 and some change.
 
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Ring end gap isn't the only thing to check. There is also the gap between the ring and the ring groove on the piston.

If it were mine, since I was already there, I'd simply put in new rings. No worry about loss of ring from rust or loss of spring tension in it from age either. You're going to hone the bore so you'll need to break in the rings anyhow. Don't forget to clean the ring grooves thoroughly on the piston.
 
I'm the "you might as well, while you're in there" kind of person. They're not too terribly expensive, and you'll at least know where you're starting from in the event that something breaks down the road.

If you get it free and cleaned up a little bit while still on the bike, do the leakdown (or a compression test). I was told that for old airheads, the common leakdown is about 8%. If it's worse than that, and you take it apart and do the end gap and that doesn't look too good either, just replace them.
 
Motor31 said:
Ring end gap isn't the only thing to check. There is also the gap between the ring and the ring groove on the piston.
Yeah, but at 18,000 miles I wouldn't expect problems there. In fact I wouldn't expect ring gap problems either. The overall condition of the piston and rings, due to the fact that they rusted together, though...

By "surface rust" what exactly do you mean? If a light honing doesn't completely eliminate all evidence of it, it's not surface rust.
 
I solved the dilimma today. I broke the ring getting it free.... So off went the rest of the rings on both sides and in went the order for new. I love old bikes so at least I'll feel like I did it up the right way.
I hones today and it's clean as new so, no worry now.
A little foot note: The finish had very little nicks so I'm leaving it original. Today I bought some buffing compound, it has shined up like new. Cool! :violin
 
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