Originally Posted by
elcyc
If the "mismatch" issue was/is common, as many of the commenters in this thread are claiming, then wouldn't chain and cassette would be sold in sets? And/or chain or cassette instruction manuals note that phenomena contextually? And/or bike books and YouTube videos and Internet articles/blogs note the "mismatch" issue?
Yes, it's common. It just stands to reason that chains and cassette gears both suffer from wear. The cassette wears more as the chain 'stretches.' So to prevent cassette wear, keep your chain lubed and replace it before it wears too much. On my recumbents, I find that I need to replace my cassettes about every other chain. My chains last longer than on an upright, so we're talking 4-6 chains. If I let my chains go longer between replacement, it might well be that every chain required a new cassette. BTW, since chains and cassettes wear together, that means running a new chain on a worn cassette can ruin the new chain in a very short time. I don't know how many miles you've put on your new chain since this began, but you should probably measure it. Pin to pin, 24 links (12 outer plates) should measure exactly 12 inches. It's be sucky to put a new cassette on and find you have the same problem because now your new chain is worn.