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E Thirteen Cassette Expander - Shimano


was £59.95£48.60
48.60 GBP

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Cassette Expander

1x Drivechains are everywhere you look this season from complete bikes to winning enduro rigs. Everyone is doing it so why should you have to miss out? With the e*13 EX Cog range extender you don't have to. Simply fit this sprocket to your existing 10 spd cassette, using the clear instructions provided, and say goodbye to your front shift setup.

Here are the basics:

It's an add-on cog to extend gear range of 10 spd. Shimano and Sram cassettes
It comes in 40t and 42t for use with Shimano cassettes and a 42t only for use with Sram cassettes
Installing your EX Cog is easy. Remove the 15t or 17t cog from your cassette & place the EX Cog on your freehub, then install your existing cassette back in place (complete instructions here)
Each EX Cog is timed and ramped specific toShimano and SRAM cassettes
The EX Cog comes with a longer steel replacement, B-limit screw for your derailleurs. Your current one won't be long enough to get the best shifting up to the new cog
Available in Black, Red, and Blue



Q: Can I use the 40t EX Cog with a 36t cassette?
A: We don't recommend using the 40t EX Cog with a 36t cassette. Shift performance will be compromised as the timing will not be correct.

Q: Can I use the 42t EX Cog on my 34t cassette?
A: The 42t EX Cogs WILL NOT work with 34t max cassettes. A 6 tooth jump is the maximum for good shifts.
Q: I have a short cage derailleur on my bike. Will that work?
A: We recommend a medium or long cage derailleur. (if you are not sure about max. derailleur capacity, check here to reference our handy compatibility chart.)

Q: Why do you only have a 42t EX Cog for SRAM cassettes?
A: The 40t is available only for Shimano as SRAM is not offering a 34t cassette.

Q: Is it hard to setup the EX cog?
A: It's really not too hard, but you are working at the extreme limits of your rear derailleur. If you have specific questions about the setup and adjustment, we recommend heading to your local bike shop.
Q: I have a really worn drivetrain. Will the EX Cog work ok on my bike?
A: Old drivetrain components could cause poor shifting performance. We recommend a new chain and a new or well-cared for cassette.
Q: What is the extra screw for?
A: It's a replacement B limit screw for your rear derailleur. The longer screw may be needed for proper derailleur set-up. If you are unsure about setting your B limit, refer to our how to guide, or head in to your local bike shop.

Q: Can I run this cog on my 2x system?
A:Indeed you can if you have the proper bits currently in your drivetrain.


Brand: E Thirteen

Product code: FW10ER10SRAM42Rz


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