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Wolf Tooth Components 40T GC Cog for Shimano

Wolf Tooth Components 40T GC Cog for Shimano
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The GC line of cassette extender cogs allows you to modify your 10-speed cassette into a wide range cassette. To achieve optimal shifting, the GCs are optimized for Shimano or SRAM cassettes.

- Compatible with Shimano 10-speed cassettes
- Compatible with all 10-speed rear derailleurs and chains
- Note that you may need a longer chain that you currently have on your bike
- Chain stretch should be less than .5 when installing a new GC
- Can be run in 2x configuration with a long-cage rear derailleur
- These fit very tight on certain Stan's No Tubes hubs like the 3.30 and the Easton X4 hubs. With a little filing and some grease they will go on.

Part Numbers

Option UPC MPN Store SKU
Silver / 40T 812719021128 SILGC40SHIM SILGC40SHIM