by Marc Basiliere
December 3, 2013
Add-on sprocket extends Shimano & SRAM cassettes
Part of what makes SRAM’s XX1 and X01 1×11 drivetrains work for everyday use is the massive 10-42t cassette’s 420% gearing spread. By going from teeny-tiny to massive, the cassettes provide 96% of the range provided by the first two ‘rings in a Shimano triple- at a fraction of the complexity, weight, and clatter. Of course, SRAM 11s cassettes are notoriously expensive: the least-expensive option retails for £300/$400 without the required shifter, derailleur, mech, or freehub.
OneUp Components has a solution. Making use of a rider’s existing 10s clutch-type mech, shifters, and cassette, their 42T Sprocket kit sits behind widely available SRAM or Shimano 11-36t cassettes after a mid-block 17t cog and spacer are removed. Crank down the B-tension screw, add a narrow/wide chainring, and shorten the chain and the result is – at least in theory – a 382% gearing range and 367g weight savings at under £100 total. The range is still shy of XX1/X01’s 420%, but a nice bump over most 1×10 setups’ 327% range. Given the price and ability to re-use a modern drivetrain and maintain a standard freehub, it’s hard to complain too loudly.
The jump from 36t to the 42t cog is the same as seen on SRAM 11s cassettes- noticeable but not unbearable. Once the 17t cog is removed, the mid-stack step from 15t to 19t might also be felt- but the system is all about finding an acceptable compromise. OneUp has tested and approved their system for use with XTR, XT, X9, X7, and X5 11-36t cassettes. Only a couple of Roval (Specialized) wheels are known not to work- see the company’s compatibility page for more details.
OneUp’s 42t Sprocket sells for $100 (£61), including shipping anywhere in the world. For the time being, purchasers can exchange their e-mail address for a 15% discount ($85/£52 shipped). For anyone intrigued by single-ring drivetrains but not quite ready to muscle a 11-36 spread ’round the hills, OneUp is presenting what looks to be a promising alternative. Kits ordered now are expected to begin shipping in January.
Who wants ratios?
|Cassette||11-36||OneUp 11-42||XX1 10-42||11-36||11-36||11-36||11-36||11-36|