sorry if you already know this but
say you run 22-18, theres much more chain so the stress is less per link than runnin 16-13 or watever, i thort bout gettin super pro burns for ma bt but a decided not to because of the chain snap issuses involves and the chain has to curl round the cogs more because the are small whitch causes more wear.
you can measure chain wear by streaching the chain right out then measurin it.
then push it together, it should still b in stright line though and take the mesurement, do this when you first get it so you can compare the wear :ermm:
tom