To prevent poor shifting and uneven drive train wear, manufacturers suggest replacing the chain before the rear cog. With the Park Tool Chain Checker, you can quickly and precisely measure the wear and stretch of any chain. Just insert the pins of the Chain Checker into two links, gently press the swing - arm gauge, and get an accurate reading from the gauge window. The CC - 2 works with all derailleur chains. For 9 and 10 - speed chains, replace at or slightly before the 0.75% reading. For 11 and 12 - speed chains, replace at or just before the 0.5% reading. Check the manufacturer's specific replacement guidelines.
Using the Park Tool CC - 2 Bike Chain Wear Indicator is easy. First, find two links on your bike chain. Then insert the pins of the indicator into those two links. After that, lightly press the swing - arm gauge. Look at the gauge window to get an accurate reading of the chain's wear. Remember, for 9 and 10 - speed chains, replace the chain when the reading hits 0.75% or just before. For 11 and 12 - speed chains, replace it at 0.5% or slightly before. Always check with the chain's manufacturer for specific replacement advice. To keep your CC - 2 in good condition, store it in a dry place and clean it occasionally with a soft cloth.
