Chain Wear - How Much Is Too Much? 0.5, 0.75, 1.0+%

buckmulligan

So during some weekend maintenance I was checking the chain on my turbo bike using my Park Tool chain gauge and it's past the 0.75% stretch marker, which comfortably slots in when testing at multiple points around the chain.

However, in reading some online guides, it seems like 0.75% might be a somewhat conservative point to replace it with some workshop guides and tools using a value of 1.0% or more. It's still shifting fine and only being used with cheapish 105 bits on my turbo trainer bike so it seems a bit overly-cautious to throw away a good chain?

Obviously I'm keen to avoid knackering my chainrings and cassettes, so what's the best advice for a modern 11-speed Shimano gear, when should I ditch it?

veronese68

I used to use a chain until shifting went to pot, then I'd have to change the chain and cassette. With the current cassette I'm now on my third chain having replaced them when they pass 0.75. Chains are cheaper than cassettes so I err on the side of caution in terms of chain wear.

keef66

I keep replacing chains at 0.75% untill a new chain skips on the worn cassette. Then I replace the cassette too. I have yet to wear out a chainring.

I may not be getting as much life out of chains as I otherwise might, but I'm not trashing the rest of the drivetrain.

The alternative is to run everything into the ground. Not sure how long that would take and the comparative cost.

As a youth I rode my 5 speed racers about a gazillion miles with only occasional lubrication, and I don't remember ever replacing a chain, freewheel or chainring. Quite chunky steel and taller teeth in those days

veryslowtwitch

Hi, I find it easiest just to check intermittently and bin and replace at 0.75+ and not waste time thinking about it. Especially if you have more than one bike you may forget to check it again for ages when it becomes way over 1%.