There are about as many ways to clean & maintain a chain as there are folks who ride bikes. All of us have our own particular regimen.
Every hundred miles or so, I twist the chain between my thumb and forefinger to get a "feel" for how much grit is in the rollers.
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When it's time, I clean the chain with a Park Cyclone cleaner, CB4 fluid, followed by several applications of dish detergent.
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It's amazing just how much crap a chain picks up:
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Before lubing but AFTER cleaning, I check the chain for wear using a Park CC-4 Gauge. You can get false readings when measuring a dirty chain due to debris in the rollers.
In this case, the chain has more than .75" of play and I'll replace it at the end of this season.
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