Cleaning my chain today before lubing and started looking closely at stuff. This bike has 2700 miles and is 105 componentry level. Of the miles, I guess 85%+ have been using the large ring in a compact gearset (50/34), maybe more since I'm rarely in the 34.

Any rate, the front large gear doesn't look right, the teeth look worn with the tops of some gone. How many miles can you expect from a crankset anyway? It is 1000 miles into the 2nd chain.

Below are shots of the crankset large gear, small gear and rear casette. From my limited experience, only the front large gear looks bad. Seems that I should get a bunch more than a few thousand miles from a crankset. This is Florida and there is sand everywhere. Am I getting fast wear because of the sand?