When to replace a chain

[Puffs]

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[Blurredman]

Good idea! I should definitely try this!!

[DAVID THOMPSON]

the covered chain on mz bikes is great
but some fail to take it apart and clean and re-lube it
in a timely manner
and do inspect it if bike has set for a couple years
as some grease sets up into a mess

[Kruh]

Another common trick is to lift the chain in the middle of the rear sprocket, if you can lift it too much both chain & sprockets need replacing.

I've heard of that trick before. But haven't had a chance to test it with a new chain and sprocket to compare it with the old.
Could you specify any further on this trick? Some rough numbers or some relation between the chain and sprocket? For exapmle, how much of the teeth the chain uncovers when pulled or something similar.

[Puffs]

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[Kruh]

Thanks for the reply.

[Puffs]

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