Hands On: Wolf Tooth Components GC 42t Shimano Cassette Adapter
Since it looks like Shimano might be more focused on competing with GoPro on cameras than with SRAM on XX1 competition, 42t cassette adapters may be here for a while. Even if Shimano were to come out with a viable answer to XX1, there would still be plenty of market for adapters like Wolf Tooth Component’s GC thanks to the ability to expand your 1x or 2x options on the cheap.
Why not just go with a smaller front chainring? The benefit to a cassette adapter is the wider spread of gears that the 11-42 provides over say an 11-36. In testing the spread offers high enough gearing for riding the road to the trails, but low enough that in most loose situations the rear wheel will struggle for traction before you run out of gears. After riding a few 42t cassette adapters for 2 months, I won’t be giving up the cassette adapters any time soon.
How does the new Wolf Tooth Components GC compare? Find out next.
Thanks to the huge profile of the 42t cog, and the aftermarket nature of the big ring, the shifting up to the bail out gear is called into question. Fortunately the Wolf Tooth Components GC offers lighting fast shifting which is a direct result of the amount of detail put into the machining of each tooth and shift ramp. This is where the GC is set apart from the competition, with smooth, silent shifts up to the 42t GC – so much so that you’ll probably look down to make sure that it is actually in gear. The shifting on the rest of the cassette is admittedly softer than stock thanks to the increased b-tension, but in my experience it hasn’t been a deal breaker. Honestly, it sort of makes the 10 speed drive train feel like you’re running 9 speed – shifts are just a bit more clunky and not as laser fast as we’ve come to love from Shimano Dyna-sys. Would XX1 shift better? Yes. But when you start adding up the price for an XX1 conversion, the $89 Wolf Tooth GC looks pretty appealing.
Anyone who was initially concerned with the OneUp or GC cassette adapters damaging the splines on your freehub body need not worry. After quite a few miles, my freehub body is looking as good as new. As an added benefit, the fit of the WTC GC is very precise around the splines which should only help to prevent any wear and tear. Keep in mind that unlike the OneUp, the GC is Shimano or SRAM specific. While not quite as convenient, Wolf Tooth mentions that trying to make a cog that shifted to their liking that would fit both cassettes proved impossible. By keeping it to one or the other they were able to fine tune the shifting teeth and ramps to each cassette for precise shifting which really shows in the final product. An added benefit of this design is the lack of any spacers needed for the GC – just remove the 17t cog and spacer from the cassette and you’re good to go.
Because the GC is Shimano or SRAM specific, the Shimano version is only compatible with 10 speed 11-36 XT or XTR cassettes, while the SRAM version (also $89) is compatible with X5, X7, and X9 10 speed 11-36 cassettes.
The GC also has a leg up on the competition when it comes to the b-tension screw since a longer, 25mm screw is included with the cog. More than just a longer screw, it is also an allen bolt which makes dialing in the b-tension easier than the stock flat head screw. A word of caution though, make sure to thread the bolt in by hand to start, it would be easy to cross thread which would result in a very unhappy rear derailleur. With the new bolt in place on my XT Shadow + rear derailleur, there was plenty of adjustment to fine tune the chain wrap so that the cage would clear the GC. For more installation advice, head over the GC tech page.
At 86 grams for the cog (minus 20g for the 17t and spacer) you end up with a cassette that is 66g heavier than stock. The GC is a bit heavier than say the OneUp (73g) which they claim is due to wanting to ensure the cog is plenty stiff and durable.
Overall, the WTC GC seems like a winner with excellent shifting, a replacement b-tension bolt, and the made in the US quality we have come to expect from Wolf Tooth. The only problem you’ll run into is getting your hands on one – all of their current shipments are sold out. WTC will be running a new pre-sale around Feb. 14 and you can sign up for an in-stock reminder on their site.
Wondering what the GC will do for your gearing? Check out the handy gear range charts WTC made up with 29″ wheels up top, followed by 27.5″ and 26″.