I have a KMC X10SL with about 2500 'hard' miles on it; training and racing.
I generally use wax lube; it's usually very quiet. I have done major cleaning on it before with dish soap and a toothbrush, and it's been generally fine.

Recently i used a spray degreaser (same company as the wax lube) and it got the chain amazingly clean very fast. so i wiped it off, applied new lube, let it dry, and applied new lube again. twice.

the chain has since become extremely loud. the RD is adjusted properly.
I feel that i have re-lubed it enough now that it really shouldn't be a lube problem. it's still very clean.

i searched and read that degreasing a worn chain will loosen the grit in the links and kind of "expose" how worn it really is.

what do you think? a sign the chain is done for?

measure it. Replace if its beyond tolerances.

Chemical degreasing removes the lube from inside the rollers. A casual lubing job doesn't lube inside the rollers very well. You really need to work the lube in to make it effective.

+1 Measuring will tell you whether this chain has life left in it. The 2500+ mileage estimate is only meaningful relative to your experience with similar chains.

FWIW, the spray solvent you used may have done a superior job at breaking down the paraffin and other components in your wax lube in comparison to what your dish soap has previously done. There's nothing wrong with that. However, while you mention wiping off the chain after using the spray solvent, you don't mention allowing time for the solvent to dry from the chain's innards. If wet solvent was still present inside the chain when you applied the wax lube, then I'd question how much of that lube actually made it to the interior of the chain or if the present solvent broke down what lube did make it there. In my warm, dry climate, I still allow several hours (or even overnight) for solvents to completely evaporate.

I use Finish Line Dry Teflon (drip) which is paraffin-based. I find odorless mineral spirits do a fine job at removing the lube, but I have also used Dupont Motorcycle Degreaser and White Lightning Clean Streak. The latter two products evaporate more quickly than OMS, but the fumes are somewhat unpleasant.

i would measure it, but i'm sitting in my apartment in front of a computer - i would like to get some info before immediately running to buy another tool.

I had used clean streak, and i didn't give it overnight to dry. however, it's been about a week - i've relubed twice and ridden over 100 miles. maybe i'll give it a bit more grease and another week. this is my first KMC chain, so i don't exactly know what to expect. My previous SRAM chains have lasted 3-4000.

FWIW, my KMC X10SL chains are always a little bit louder the first ride after degreasing. Then it quiets down after a while.

And I use mineral spirits exclusively as degreaser.

This. And bathe a chain in mineral spirits for a cleaner and easier way to get the grease off. If this is the first time you have cleaned your chain thoroughly, adjust your schedule to do it monthly, at least. Spray degreaser is like a band aid - you will be happier if you take a little more time to heal the wounded chain.

You don't need a tool. Sheldon tells you how to do it with a ruler at the bottom of this article. Long live Sheldon!

https://sheldonbrown.com/chains.html

+1 on the ruler method. I bought a nice 15ins steel ruler from Staples for $3 for this purpose.

is he saying the the links should match up with the inch marks? Sheldon is great but his writing style was too verbose and hard to follow

Edit: well, if he's saying that each inch mark should line up with the same place on the chain, then the chains on both my bikes are pretty decently worn despite only having about 2500 miles on them. One is a KMC X10SL, and the other is a SRAM PC1070. I have an extra 1070 lying around - i'm going to swap that and see if it fixes things.

https://www.kronowit.com/bicycling/chainstretch.html

2500 miles is a lot for a 10sp chain even if it has been lubricated with oil. Wax based lubes aren't as good.

i re-measured the chains.

my SRAM 1070 chain is stretched about 1/16 of an inch. that'll get replaced.
my KMC X10SL - the really noisy one - actually appears to be in good shape. Hard to believe since i think i have done harder riding on this one this year.

So, I'm going to try an experiment:
I took the KMC chain off the bike and degreased the holy hell out of it again.
then i rinsed it thoroughly and let it dry.
then i sprayed it again with a bunch of degreaser and repeated the process.
then i put it in my dishwasher and let it go through a cycle.
it's currently sparkling clean and drying out.
if there's any dirt still in it, it's not coming out.

i'm going to give it another shot with a few coats of new lube, and we'll see what happens. hopefully i can learn something about this process.

Keenly following this. Last week I took my bike in for the free drive-train cleaning and it's been annoyingly loud since I got it back. It's really sounds like it's rubbing on something and this gets noticeably louder when I'm pushing is (climbing, sprinting, etc.). It looks really clean, but I think it's a little dry. About 1500 miles on it.

well, turned out that i couldn't give it additional coats because i was almost out of lube. so, on a completely dry chain, i put a little more than one drop per link.

i took it out today in pouring rain and it was much quieter than it was a few days ago.

Well you're definitely going to need to get some new lube now...

yep!

I threw science and argument to the wind when I found out several guys that routinely shellac me on the group rides are using "white lightning clean ride". It kind of makes sense for here - rarely rains if ever but it's very windy and can get dusty. Come to think of it, I've put 1500 miles on that bike and I don't think it's been in rain once.

Anyway - after following the instructions on the bottle, all the racket my drive-train was making completely disappeared. I wiped down and put on another coat after my 20m run for good measure. If it holds up through Saturday's century then that will be good enough for now.

Can I ask what spray on degreaser you used? Some citrus based ones are water activated and you need to apply, rinse with water then lube. If not they won't have had a chance to break down the grease and will leave more residue thatn necessary.

i use white lightning "Clean Ride" as lube
the degreaser is "Clean Streak" by the same company. works extremely well, i assume because they know what solvent to use for their own lube.