Can't Afford XX1? Massive 42 Tooth OneUp Components Sprocket Could Be Your Solution 20

Inspired by SRAM's well-regarded but pricey XX1 drivetrain, more and more riders are making the jump to a single ring setup these days. With increasingly available narrow/wide chainrings and clutched derailleurs, many are forgoing the real deal XX1 or X01 systems. Regardless of how it's achieved, the major benefits of a 1X system include less weight, better chain retention, less friction and greater simplicity. This often comes at the expense of gearing range, though, especially if you're using a standard 11-36 tooth cassette out back. Enter OneUp Components and their new 42 tooth sprocket, a $100 solution to expanding that range.

CNC machined from hard wearing 7075 aluminum, the 42 tooth sprocket fits behind most 10-speed 11-36 cassettes, displacing one sprocket from the main cluster. The end result is a 11-42 tooth cassette with enough range to help you get up the steepest of hills (depending on the size of your front chainring, of course).

OneUp works with these 10-speed cassettes:


  • XT (CS-M771-10 11-36)
  • XTR (M980 11-36)


  • X5 (PG-1030 11-36)
  • X7 (PG-1050 11-36)
  • X9 (PG-1070 11-36)

OneUp claims that any medium or long cage 10-speed SRAM or Shimano derailleur will work. The 42 tooth sprocket is said to play nice with 2x10, too, provided you're using a long cage derailleur. For SRAM you can get away with a 14T difference in front rings (like a 28/42) and for Shimano you can manage a 12T jump (like a 28/40).


  • Uses standard freehub driver bodies
  • 12 upshift points optimized for most 11-36 cassettes
  • 10-speeds (with 17 tooth removed): 11-13-15-19-21-24-28-32-36-42
  • OneUp adapted cassette weight increase: 51g
  • Typical 3X to 1X system weight decrease: 367g
  • Cassette range improvement: 17%
  • Colors: Black or green

MSRP is $100. They'll be shipping as early as mid January with free shipping worldwide.  Visit for more details.


View replies to: Can't Afford XX1? Massive 42 Tooth OneUp Components Sprocket Could Be Your Solution


In reply to by astrizzle

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