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The e*thirteen have created the perfect chain range extender cog Scram 42T to add to your 10 speed cassette to increase your climbing prowess.
The e*thirteen have created the perfect chain range extender cog Scram 42T to add to your 10 speed cassette to increase your climbing prowess.

eThirteen Range Extender EX Cog - Sram 42T

£49.99  £54.95  9% off
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It is your responsibility to ensure that the item is returned to us in a safe and secure manner, we suggest that you use a recorded postal/courier service. Please ensure that the service you use covers the value of the goods in the parcel.

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eThirteen Range Extender EX Cog - Sram 42T Information

Season : B

Brand : E.Thirteen

Code : FW10.ER-10SRAM.42.

If your doubtful about going 1x10 due to the lack of hill climbing options, then the e*thirteen Range Extender Cog is for you. With its massive size (42T), the cog is designed to replace your 15/17T cog in the middle of your cassette to create the ultimate hill climbing gear.

The advantages of using this cog are clear: less weight, no more front mech and smoother gears without the massive price tag of the latest 1x specific drivetrains.

An EXA+ anodised aluminium construction helps to resist flex under heavy power and has been shaped to work exclusively with Sram cassettes with a 34T cog for perfect shifting performance.

Available in three colours to suit any bike.

What's In The Box

  • EX cog
  • Longer B limit screw


Why do you only have a 42t EX Cog for Sram cassettes?

The 40t is available only for Shimano cassettes as Sram do not offer a 34T cassette.

I have a short cage derailleur on my bike. Will that work?

We recommend the use of a medium or long cage rear mech to allow space for the larger cog.

Is it hard to setup the EX cog?

The installation is simple, although you are working at the extreme limits of your rear mech. If you have any problems we recommend fitting at your local bike shop.

I have a really worn drivetrain. Will the EX Cog work ok on my bike?

We recommend the use of a new chain and cassette when fitting the EX Cog to ensure good shifting performance.

What is the extra screw for?

The EX Cog is supplied with an extra long B limit screw, this may be needed for proper mech set-up. If you are unsure about setting your B limit, we recommend heading to your local bike store.

Technical Information
  • Cog Material - EXA+ Aluminum
  • Thickness - 5mm
  • Compatibility - 10 Speed
  • Ring Size - 42T
  • Colors - Blackout, Red, Blue
  • Weight - 77g
Sizing Information
Professional Opinion
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