Originally Posted by
rpenmanparker
Not that you wear out a ring, but that it is the big ring. Folks who have a 12 tooth, 2nd to smallest cog in the back and turn high cadence (~95 rpm) spend more time on the small ring (potentially up to almost 25 mph) and wear that out faster. Also the small ring has fewer teeth and wears out faster for that reason too. Your experience suggests that you turn the crank a little slower OR you ride much faster. No matter. Lots of valid riding styles.
I run a 50T big ring with a 12-23 cassette. Most of the time I spin at about 86rpm, in the 15-18 cogs.
West of Phoenix is pretty darn flat, and the hills that we do have are short sprints. I'd rather crosschain it for a moment, than shift into the small ring.