Review on 🔗 Efficient Chain Checker: Park Tool Ensures Optimal Performance by Sean Reddy

This tool measures chain wear and is very easy to use. There are two metal pins on the underside of the tool, one pin is attached to the lever and is offset so that the distance between the pins changes as the lever is moved. This allows you to measure very precisely how much the bicycle chain has stretched. The stretch is visible through a small window. The tool is machined from solid aluminum and painted (not painted) in an anodized color. No plastic or fragile parts. The tool never wears out - you'll need it for the rest of your cycling life. Chains have a succession of narrow and wide links. Each pair of narrow and wide links in the new chain measure exactly 1.0 inch from pin center to pin center. If you were to use a ruler to measure 20 links (10 "pairs"), it should measure exactly 10.0 inches on a brand new chain. The chain will stretch as the pivots wear. 1/16" is fine, but at 1/8" it's time to replace the chain. But using the park tool is easier and faster than using a ruler. Set the lever to position "0" and install the tool. on your chain (tighten the chain slightly to get an accurate measurement - chain slack measurement is not accurate) so that the pins on the tool are between your chain links. Push the lever all the way down, and then read the strain reading through the window on the tool. A brand new chain will measure 0.0 - any used chain will have some stretch. Values below 0.5 are considered normal/acceptable wear (the tool reads 0 to 1.0 inch in 25 increments), but above 0.5 means your chain will need to be replaced soon. I change my chains when they read .75. why do you care Chains are relatively inexpensive and easy to replace, but if not replaced, the chain will begin to slip and jump - usually under heavy loads, e.g. aggressive trail ascent (just when you _don't_ want it to happen). An overstretched chain will also wear out the sprockets - this will affect the chainrings slightly, but can affect the rear freehub or cassette more quickly and is more expensive to replace. If you ride aggressively on the trail, you should check your chain. about every 100-200 km running. If you drive more cautiously or only on mostly flat roads, you may only need to check every 300-500 miles. I give this tool 5 stars (and I'm not the type to give only 5 stars because I bought it myself) because it's easy to use, easy to read, accurate and made of durable materials and not cheap plastic parts, every detail (including anodizing the aluminum instead of painting it so it doesn't even need to be painted). off.) They did everything right when they made this tool. I couldn't ask for more.