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Wolf Tooth 42T GC Cog for Shimano

$54.98 - $59.98

Wolf Tooth 42T GC Cog for Shimano

The GC42 cassette cog is so big that when machining the first batch, the machinist thought he made a mistake! If being big is cool then the GC42 cassette cog is the coolest cog around. This cog is made with the precision and finish our customers have come to expect from WTC.

This cassette sprocket is for use only with Shimano brand 10spd XT & XTR cassettes. It is NOT compatible with any other brand or model of cassette. The shift points are properly timed to the tooth locations on the 36t Shimano cogs for optimal shifting performance.

Use of this cassette sprocket requires removal of the 17T cog & spacer from your cassette.

A longer (25mm) “B-screw” on the rear derailleur isn't needed in most cases. If you do need a longer B-screw to get the correct amount of clearance, you can order them directly from WTC or go to your local hardware store and pick up an M4 x 25 socket head cap screw.

You may need a longer chain that what is presently on your bike. Make sure that when shifted to the 42T cog, there is still some amount of forward travel possible with the rear derailleur cage. This is especially important on bikes with rear suspension. We have tested with Shimano, KMC & SRAM chains – all function well.

  • Only compatible with Shimano XT 11-36t (CS-M771) or XTR 11-36t (M980)
  • NOT compatible with SLX 11-36 cassettes because the 17t cog cannot be removed.

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Showing Questions 1-2 of 2

Q: Is this product compatible with the Shimano Zee FR rear derailleur?

A: This cog is not compatible with short cage derailleurs.

Q: If I use 30T Chainring, would that be compatible with the Shimano Zee RD and if not, which might be the best suggestion for rear derailleur?

A: You will need to use a long cage derailleur.

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only way to go for 1x10 - Dec 27, 2015

1 2 3 4 5
5 out of 5 stars
Greenfield, MA

upgraded my scott spark to 1x shifting. i ended up sheding 1.5 ponds and with little to no loss of low end with this cog. Easy to install only took about 10-15 minutes

0 out of 0 people found this review helpful
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Cheap XX1 - Apr 23, 2014

1 2 3 4 5
5 out of 5 stars
Denver, CO

This product is an awesome cheap alternative to XX1. You get almost all of the gearing for a much lower price. I live in Colorado and this works great for the mountains with a 32 tooth chainring.

2 out of 2 people found this review helpful
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Just do it. - Apr 10, 2014

1 2 3 4 5
5 out of 5 stars

I wanted to go to a 1x system for a while but didn't want to spend the $$$$ on an XX1 drivetrain or ditch my beloved Chris King wheels which are not compatible with XX1. I combined this with a Raceface N/W chainring, SLX shadow plus deraileur, and XT cassette and couldn't be much happier. The shifting between the 36t and 42t is flawless. The only small complaint is the removal of the 17t cog is a bigger gap than I would like, but it is rarely an issue on the trail.

2 out of 2 people found this review helpful
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