SRAM's 1x11 system (XX1/X01) has many exceptional characteristics, including simplicity, functionality and smoothness, but the price tag and the requirement of mostly using a full set of SRAM parts for the drivetrain has kept many people away from enjoying the benefits of the product. It didn't take long for third party companies to jump into the fray to give consumers workarounds for the 1x11 system, so we now have cassette adapters from Wolf Tooth Components and OneUp Components that use portions of a 10-speed 11-36T along with an additional large cog to give a wider gearing range to more closely emulate the SRAM 11-speed 10-42T cassettes.

The Wolf Components GC 42T cog comes in either a Shimano and SRAM specific model, and fits Shimano XT and XTR, and SRAM X5, X7 and X9 11-36T cassettes, and you remove the inner 17-tooth to keep it as a 10-speed system. Another interesting aspect of this system is that you can run it as a 2x10 if desired, though I am not sure what front gearing you might use. The GC 42T cog is made from aluminum, weighs 85 grams, retails for $89.95, and comes with a longer (25mm) steel "B-screw" with a hex head. The cog has six special ramp section around the circumference to aid in shifting, and to keep the cog from digging into the soft material of most freehub bodies it has wide tabs by the spline for better load distribution.

My initial test setup on my Ibis Ripley 29er is an XTR 11-36 cassette, a medium caged X0 Type 2 rear derailleur and an E*thirteen TRS+ crankset with a 32T chainring (original 2x10 was 24-34T).



Installation

I pulled the XTR cassette off the rear hub and tossed out the 17 cog and its accompanying spacer. I added the GC 42T cog to the hub, and then the rest of the XTR stack (minus the 17t), and cranked it down to specs. I liked that the GC cog had a small dot pointing at the notch, so it made it easy to line everything up on the free hub body. Swapping everything out increased the XTR cassettes weight by 65 grams (85g for the 42T cog - 20g for the 17t/spacer), which should be about the same weight difference (give or take) for any of the appropriate models since the 17t is usually made from stamped steel.

Note: I located an old Shimano 16t cog in my parts bin, so I swapped out the 15t with the 16t to create a more even range in gearing: 11-13-16-19-21-24-28-32-36-42. The difference in shifting using the 16t vs 15t isn't really that significant, but does make for slightly smoother transitions.



I wasn't sure how long of a chain I might need for the 42-tooth rear and 32-tooth front combination, so I bought a new 120 link SRAM PC 1071 chain, and ended using 112 links plus the PowerLock connector. As shown above, that chain length worked fine for both the highest and lowest gearing options.

I replaced the standard B-tension screw with the kit's steel 4x25mm hex bolt, since it gave me additional length if required, and the toughness of a non-alloy bolt and the functionality of a hex head. I had to play with the B-tension until it shifted smoothly between the 36T and 42T cogs, else it would shudder, and I ended up getting it close to its limit to keep the pulley the proper distance from the cog. I also found it was best to alter the B-tension screw when it wasn't under pressure, so downshift to the middle of the cog when making major changes. According to Wolf, if you're using a Shimano derailleur, you might need to reverse the B-tension screw to gain additional length.

Continue reading for more on the Wolf Tooth Components GC 42T and full photo gallery.



First Impressions

So how does it ride and shift? It works surprisingly well, and in direct comparison to the 32T to 36T up shift, there is a slight loss of smoothness, and a bit more of a thunk during the 19T to 15T drop due to the missing 17T (same goes for 19T to 16T in my secondary test); otherwise, I didn't notice any outstanding issues. I have taken it out for several days of riding, and it shifted flawlessly, in fact; I would be hard-pressed to realize that I had this gearing installed on the bike. I cranked things under heavy loads on some pretty steep terrain, in both loose and smooth conditions, and the shifting and power transfer worked fine. We had some adverse weather conditions, so it got some snow and mud tossed into the system during shifting, and continued to perform admirably. I certainly liked not having to roll up and down through the front derailleur to get my desired gearing options, and I felt as though I could spin better with the larger chainring compared to a granny sizing.

How does the shifting compare to the OneUp 42T cog? It shifts with slightly more precision and crispness than the OneUp, and although that's noticeable, it isn't that significant in the grand scheme of things. I am not sure if it's the way Wolf has done the individual teeth design or their 6 ramped sections, but whatever they have done makes a subtle difference. Wolf found that the timing of the shifting ramps is extremely critical and SRAM and Shimano are very different, so they designed Shimano or SRAM specific versions to offer the best possible shifting performance. The OneUp cog can be used with either vendor by moving some included spacers to specific locations.

How does it compare to SRAM 1x11? The overall shifting isn't on par with the smoothness of the 11-speed design system, but it does more than a decent job, and I never had any real issues with it. Obviously, the 10-speed rear derailleurs are optimized for a 36-tooth maximum, and weren't designed to be used 42T, but they work surprisingly well, although the smaller cog shifts are slightly clunkier due to the B-tension setting.



Final Thoughts

Once I had the derailleur tuned properly and chain at the correct length, the GC 42T system has worked exceptional well, and I really didn't notice any difference in usage compared to my original 2x10 normal setup (11-36T rear and 24x34 front). I think this simple system, with its low-cost and fewer part swap outs will appeal to a lot of people. The $89.95 price, and maybe a new chain, clutch derailleur and a narrow-wide chainring will get you a pseudo alternative to the SRAM 1x11 wide range of gearing. The Wolf Tooth Components GC 42T cassette adapter is a well-made product, and their subtle ramping design makes for more precise and smoother shifting, and makes any 1x10 and 2x10 have a much wider range of gearing, allowing to compete against SRAM mighty 1x11 system for a fraction of the price.

Pros

  • Wide range 1x10 gearing
  • 1x and 2x usage
  • Low-cost and fewer part swap outs compared to SRAM 1x11
  • Kit comes with a longer steel B-tension screw with a hex head
  • $10 less expensive than the OneUp Components 42T cog

Cons

  • Missing 10T cog of SRAM 1x11 cassette
  • Clunky 19T to 15T shifting (due to missing 17T)
  • General clunkier smaller cog shifting due to B-tension setting
  • SRAM or Shimano specific cogs - OneUp Components 42T cog does both

Specifications

  • Price: $89.95
  • Weight: 89 grams
  • Size: 42 tooth only
  • 11-13-15-19-21-24-28-32-36-42
For more information visit: www.wolftoothcycling.com.