I put more than 20k on my recumbent's bottom bracket and the cranks have 34k on them. The chainrings have been replaced three times; rear cassette twice; five chains, maybe six.
david boise ID
I do have to ask why you changed your chainrings that often? My experience is that under normal road use, chainrings last at least 20,000 miles and often myuch more. I've gotten 30,000+ miles on several Shimano road cranks chainring sets and they still shifted cleanly and there was no chain skipping and, no I don't change chains all that often either.
The only truly worn out chainrings I've seen were on my son-in-laws bike. He is a racer and very strong but it still took him 25,000 miles to wear them to the obvious replacement point.