Shimano TL-CN42 Chain Wear Indicator Tool

The Shimano TL-CN42 Chain Wear Indicator Tool is a must have in your tool box.  This tool is easy to use and understand so there’ll be no question when your chain is due for replacement.

Who’s this item for: Workshop mechanics and home enthusiasts.

Chain compatibility: This will work with 7-12 speed chains. 

How does it work: There are pictograph instruction on the side of the TL-CN42.  The two steps are as follows:

1. Drop the ‘split section’ labeled with the  #1 into your chain (between two rollers). 
2. Pivoting off the ‘split-section’ try to drop the end labeled #2 into the chain. If it fouls on the roller the chain still has life left in it.  If it drops into the chain, the chain is due for replacement. 

Materials: Premium laser etched steel.

Dimensions and Weight: The dimensions are unknown but it weight roughly 35-grams.

Pros: Designed and manufactured by one of, if not the largest drivetrain manufacturer in the industry.  You know it’s going to be quality.

Cons: This style of chain wear indicator doesn’t give you an indication of how much ‘life’ you have left in your chain.  This simply tells you if it’s ‘good’ or ‘bad’.