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Press Release

It's been a tough year, we know. Beer prices are creeping up, tires have not gotten any cheaper, and it's still over $1000USD to get a brand new 1X wide-range 11spd. drivetrain on your trail bike. And what about that 1 year old 10spd. clutch derailleur you bought just last year?

Here are the basics:

  • It's an add-on cog to extend gear range of 10 speed Shimano and SRAM cassettes.
  • It's for the guys who are ok with ten speed and don't want to spend @$1000USD to go to 11 speed and get a 42 tooth cog.
  • The 42t is compatible with 36t max cassettes while 40t is compatible with 34t max cassettes.
  • Two different shift timings are available for the 42t: Shimano or SRAM.
  • 40t is available only for Shimano as SRAM is not offering a 34t cassette.
  • Cogs come with longer replacement, B-limit screw for derailleurs. This helps so the B-limit is not maxed out. This may not be needed on some 40t setups. It depends on exactly how the dropouts are positioned.
  • Chainwrap capacity will be an issue for those wanting to use double cranksets. (see our compatibility chart)
  • Cassette Compatibility: We tried to get as much info as possible on this. (see our compatibility chart) If there are cassettes that we missed, let us know and we will add them.
  • We do not recommend using the 40t extended range cog with a 36t max cassette. The shift timing is not optimized for this use and will offer sub-par shifting.
  • 42t extended range cogs WILL NOT work with 34t max cassettes. The design of the cog will interfere with the back of the original cassette.
  • Available in Black, Blue, or Red.


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. Please visit our compatibility chart online in our tech area for proper compatibility.

Watch the e*thirteen Facebook page for updates.


E*thirteen™ and the Hive™ design and manufacture class-leading wheels, pedals, cranksets, chainrings, bottom brackets, drivetrain protection, and chain retention products for discerning cyclists worldwide. For further information contact your preferred distributor, Hive USA Sales at 1-800-801-9936, Hive EU Sales at +49-861-211-77-145.

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