Depends on the quality of the chains, for the most part. High quality chains last longer than cheap chinese crap.
Depends on whether the chains/sprockets are cleaned and lubed regularly. The overall weight (passengers and cargo) makes a difference. Heavy weight causes more stress on the chains.
Road conditions, too. Pavement, for example, causes more friction during a turn, thus more stress on chains.
Many causes contribute to chain wear. There is no specific answer.
It was suggested my chains might last 400 hours. I changed them out at 300. There was a bit more life in them but I wanted to install new ones anyway. 400 might have been attainable, so I'm saving them for back-ups. BTW my aatv us a Max IV.
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