The 11-speed drivetrain rolled like a freight train into the mountain biking world when SRAM released their 1×11 XX1 system, and its now joined by the just released X01. The system uses various front chainrings (28T-38T) combined with a 10-42T cassette for its 1×11 gearing. 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 1×11 simplicity and smooth shifting of SRAM’s excellent product. It didn’t take long for third party companies to jump into the fray to give consumers workarounds for the 1×11 system.
The first workarounds were for 1×10 gearing using the current 11-36T cassettes combined with narrow-wide chainrings from Race Face, Wolf Components and others, along with a clutch rear derailleur (SRAM Type 2 or Shimano Shadow Plus). Next came cassette adapters that use portions of a 10-speed 11-36T, and replacing certain cogs to give a wider gearing range to more closely emulate the SRAM 11-speed cassettes. One of the first offerings was the General Lee cassette adapter, which replaced the last four 24-36T cogs with a 25-40T, but it only works with SRAM 1030, 1050 and 1070 cassettes, and costs $200. There are few other options on the market, including the Recon 11-40T cassette, and a couple of smaller companies operating out of Europe with cog replacements of some sort.
The latest and most interesting alternative is OneUp Components single 42-tooth cog, which will come out in January and only costs $100. The OneUp 42T cog fits at the end of the Shimano XT and XTR, 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 2×10 if desired, though I am not sure what front gearing you might use. The cog is made from 7075-T6 aluminum, weighs in at 70 grams, and has 12 up shift points. To help prevent the cog from digging into the soft material of most freehub bodies, the cog has wide tabs for a better load distribution.
The initial 2×10 setup on my Ibis Ripley 29er was a Shimano XTR 11-36 cassette, a medium caged SRAM X0 Type 2 rear derailleur and an E*thirteen TRS+ crankset with 24-34T chainrings.
For the first 1×10 test, I used the existing 34T front chainring and the OneUp adapted 11-42T cassette. I left the rest of the 2×10 components attached, to make initial testing easier, and I never used the front derailleur or shifter for anything.
For the second test, I removed the front derailleur, front shifter, inner 24t chainring and replaced the E*thirteen 34t chainring with a new Pacenti 32t, which saved 355 grams. Since adapting the cassette to 10-42T adds 50 grams, I therefore saved 305 gram (.67 lbs) over the 2×10 set up that I started out with.
Continue Reading on the Next Page for our First Impressions and Installation of the Product…