@chris1388 ohhhhh yes, many times. In a way it’s an inevitability if you run the same chain for a long time.
This Is much more common on 4 stroke applications where a split sprocket is used, as any irregularity in the sprocket half alignment can stretch the chain. Setting aside that situation, other things that can stretch the chain asymmetrically could be poor sprocket alignment, throwing the chain, debris getting into the chain, and (we suspect although no real proof) hard lockup under braking in higher horsepower classes.
All of this to say, asymmetric stretching of chains is not necessarily an inevitability, but it certainly isn’t abnormal to see. And, as we talked about before, the degree to which it affects performance is debatable, but anything that hurts rolling resistance can’t be a positive thing.
I will say I’ve been able to undo some of the tight- loose issue on chains by running the chain tighter for a session to stretch the tight section back out. It definitely isn’t an exact science and isn’t something I’d recommend, but it can kinda work…