Ring chains are only provided lubrication at the pin/bushing friction point. The roller/bushing and roller/sprocket tooth areas need lubrication as well.
As do the sealing rings themselves.
All those who feel that a ring chain is maintenace free and completely lubricated from the factory are simply misinformed, or can't read. Go to ANY chain mfg site and see what they say about the lubrication recommendations of their ring chains. Is there one who says they they do not need to be lubricated?
If you can't find a mfg who says that their ring chain needs no lubrication, then it would be pretty easy to conclude that you may not be quite as informed as you thought you were.
And those who think that the elastomer rings can keep penetrants out are simply mistaken. WD-40 has little to no lubricating qualities, yet folks seem to think it is the holy grail of chain lube. And, as mentioned, when a ring is cracked or torn, WD-40 will do nothing but help the lubricant to become softened, making it easier for it to leave the area.
Using a penetrant that ius fortified with barrier lubricants would be a much better situation for when the rings fail. And they will fail.
I see so many anecdotes of folks who swear by their ring chain...of course they seem to have problems with their sprocket teeth deforming...but that has to be due to the cheapo sprockets they were using, yes?
NO...as also mentioned, a sprocket will stay intact as long as the pitch of the chain is within specs.
I have also, on several occasions, had the opportunity to have this conversation while having the items available for inspection. It never fails...whenever I have a disscussion with a foaming-at-the-mouth ring chain/WD-40 advocate, all I do is ask them to remove the chain and inspect it. Without fail there will be one or more (usually more) sections of their ring chain that is kinked up and will not flow as well as the rest of the chain. Why is this? Because they have violated rings in that one or more section...which has allowed the lubricant to come out, and grit/water to come in. Sure, the other sections of the chain may well be in spec., but it is that one bad section that will eventually pass it's mismatched pitch along to the sprocket teeth..ALL of the sprocket teeth, and will eventually wear out a good set of sprockets.
Most times folks come away with quite a bit different feeling about the value of a ring chain.
Folks have misconceptions about sealing ring chains.
They have their place...which is when you ride in adverse conditions...but they are quite a bit more "high-maintenace" items than a standard roller chain is.
Folks who feel they require less maintenance, are only kidding themselves.