deacon- I'm a little puzzled as to why you have so many chain problems. How tight do you have the chain? Have you tried replacing the nuts and bolts on the tensioner with good hardware and that includes using the cupped washers behind the two tensioner pieces?

In well over a thousand miles I have only had "annoying noise" as a problem with my tensioner and that was mostly due to not being able to perfectly center the sprocket.

If we could get to the bottom of your tensioner problems I think you'd be a lot happier with your motorized bicycle overall.

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If it ain't broke, and you mess with it long enough, it will be.