Wolftooth Components – GC42 10 speed Cog

wolftooth components gc42 on rock

When I built up my Krampus last spring, I slapped an X9 – one by ten drive train on it, because XX1 was out of my budget. The new 29+ Krampus completes were spec’d with a 1 x 10 so I wanted to try and see if this new paired down drive train would work for me. After the first month of testing, it was clear to me, that I needed a gear easier than the 30/34 that I was running. I tried to get information about how to run a double on the Krampus and again ran into a budget issue, since it looked like the only way that it would work, would mean a new crank. I’m a big fan of the RaceFace Turbine crank that I used to complete my one by ten drive train, so I lent the bike out to Zito for testing and kind of forgot about it till this spring.

This spring, I’ve been riding the Krampus as my regular trail bike and while I can climb everything on my home trail, I would like to have the bail-out gear that the Sram 11 speed cassettes employ, for when I’m tired or have 40 pounds of camping gear strapped to the bike. (I know that some of you are saying ‘weak sauce’, but hear me out). So I read about Wolftooth Component’s GC42. The Giant Cog 42 tooth ring trades space with the 15 tooth ring and spacer on a Shimano 10 speed cassette. The GC42 resides on the innermost position on the freehub. The three pictures below shows how it all goes down.

wolftooth components gc42 collage

I talked with Brendan Moore at Wolftooth and he made sure that I had a type 2 derailer and set me up with everything that I needed to make the upgrade, including a longer B Tension screw (That I didn’t need to use). I replaced the chain with a Connex 10 speed chain made by Wippermann and married the GC42 with a brand new Shimano 10 speed cassette.

Everything you need to make the switch

Everything you need to make the switch

I decided it was time to change my chain and cassette, because there were some shifting issues on a couple of the cassette rings. When I put all of the new parts on the Krampus, those problems didn’t go away. They just migrated to the smallest cogs on the cassette. The new GC42 worked great, but the two smallest cogs were skipping intermittently. With all new parts and those symptoms, I guessed that the derailleur hanger was misaligned, so I took it to Grant at Zion Cyclery. They have a D-Hanger Tool over there, and sure’nuff….he realigned the hanger and everything shifts like bang-bang-bang! I’ve put a hand full of rides in on the new parts and I have to say, it shifts like it should…..extremely well! I’m running a Woolftooth Components 30 tooth drop-stop chainring with a RaceFace Bash Guard on Turbine Cranks. A Connex 10 Speed Chain with a Sram x9 – type 2 – Medium Cage Derailleur and a Shimano Cassette married to the GC42.

wolftooth components gc42

I’ll tell you this…..the GC42 is just what I needed to make my 1 x 10 drive train work for me – it was the correct move for both the gear inch and shift quality characteristics that I wanted. Now all we have to do is put lots of miles in and see how things are rolling at the end of the season. Stay tuned and we’ll write  a longer term review later this fall.

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3 Responses to Wolftooth Components – GC42 10 speed Cog

  1. Adam Jay June 16, 2014 at 9:24 pm #

    How do you feel about the jump in the high end of the gear range from the lost 15t cog?
    I’m leaning toward a GC42, but wonder if I would be okay with the jump, considering I’d probably only ever need that gear on the pavement.

    • Gomez June 17, 2014 at 11:15 am #

      It’s the end of the world as we know it……and I feel fine…

  2. Antoine July 16, 2014 at 2:17 pm #

    Gomez is a great handle, but “Weak-Sauce”, that has a certain ring to it…

    I like the sound of this system, 11-speed chains scare me.

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