I've got a new "used" bike on the stand and the chain won't sit correctly on the chain wheel, as seen below:
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You will not be surprised to know the chain is very worn; the rear mech is also very erratic. I'm guessing the chainwheel is worn beyond usefulness, and that being the case, the bike has lots of other problems so we'll probably strip it down for parts.
However, I'm aware I may be missing something:: does anyone else have an alternative idea of the cause, and a possible solution.
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