Originally Posted by
gauvins
I currently rotate two chains. They have 5500+kms and show approximately .25% stretch. So if I were to run the drivetrain to, say, 1.5% stretch, that would translate into 33000kms or 20,000 miles.
I have found that chains don't wear at a steady rate over their life. In my experience they show slow wear for most of their life and then go quickly once they get to a certain point. So it takes a chain most of it's life to reach 12-1/16" for 12 links and then gets to 12-1/8" in a small fraction of that time. As a result I don't really think you can project how long a chain will last by projecting the same rate of wear into the remainder of it's life.