Seems like wear to me, but I'm not really sure.

Put it this way: if those were mine, I'd retire them. Lots of sharkiness, and a few have been partially chipped off.

DD

Yes, they are worn.

Middle ring is definitely a goner. I'd still roll the dice on the big and granny rings, but wouldn't shed any tears if they skipped and I had to start with a new set.

If they still shift well and transmit power uninterrupted, they could be ready for lots more service imo.


With a new chain, a badly-worn freewheel cog will skip under power, while a worn chainring usually only has a rumbling sound under hard pedaling with new chain.


Use caution while testing for the amount of pedaling force that this chainset can sustain with whatever chain you put with it.

Yes they are worn out. There isn't really a huge downside to continuing to use worn out chainrings, as dddd points out, but even so I'd replace them myself.

How many miles on these? It's possible you may be using too much lube, or not cleaning your chain often enough.

Looks like someone was bored when they posted this. No, really, they're just fine old chain-rings with lots of patina.

I'm working on a restore of the 24" MTB I had as a kid. A nickel-plated Mongoose ATB. Hard to believe my 10-14 year old self put that much wear on them!

I think I'll just replace the middle ring given I have no idea if my own 10-year old kid will even want to ride a 30-year old bike.

I’d also call the granny ring toast even if it is TA ring, or you could rotate it by one bolt. Note the bigger tooth gaps on that ring in locations perpendicular to the crank arm, as well as the wear on surface below the teeth.

You wouldn’t want your kid to crash down when the chain skips just as he’s standing to push up a steep hill!

The granny ring transmits more torque than the other rings, so always use a stainless granny (Rivendell sells a Sugino version) on my bikes, but maybe this project doesn’t justify that expense.

Can you amplify on the too much lube comment?

Sure, it was a very common thing I used to see when I was a mechanic. People would love their bikes to death by oiling them before every ride. A wet chain attracts a lot of dirt and grit, which effectively acts like a grinding paste. This wears everything out prematurely.

The magic chain oil hawkers of the present day exacerbate this with their recommendations. "Must be reapplied every 100 miles," is an example from one well known manufacturer. Pttthhh. Ridiculous. Better to err on the dry side.