OneUp Components 42 Tooth Cog

by Brian Mullin on November 30, 2013

Photo courtesy of  OneUp Components

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 10t-42t cassette for its 1×11
gearing. The price tag and the requirement of using a full set of SRAM
parts for the drivetrain system has kept many away from enjoying the
benefits of the 1×11 simplicity and smooth shifting of SRAMS’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 11×36 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 10t-36t cogset, and replacement 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 a hefty $200. There are
few other options on the market, including the Recon 11-40 cassette, and
a couple of smaller companies operating out of Europe with cog
replacements of some sort.

latest and most interesting alternative is OneUp Components single
42-tooth cog, which will come out in January and only costs $100. 

Photo courtesy of  OneUp Components

OneUp single cog fits at the end of the Shimano XT and XTR, SRAM X5, X7
and X9 cassettes, and then 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.

Photo courtesy of  OneUp Components 

keeping a 10-speed system with a wider gearing in the rear, you can
keep the costs down and decrease parts swap outs. There isn’t a need for
a new hub body, just a narrow-wide chainring and perhaps a clutch rear derailleur, and for many consumers, they’ll already have the latter component.


  • 10-speeds: (11-13-15-19-21-24-28-32-36-42)
  • 42T sprocket material: 7075-T6
  • OneUp adapted cassette weight increase: 51g
  • Cassette range improvement: 17%
  • Availability: Mid January 2014
  • Compatibility – Shimano XT (CS-M771-10 11-36) and XTR (M980 11-36), SRAM X5 (PG-1030 11-36), X7 (PG-1050 11-36) and X9 (PG-1070 11-36)
  • Price: $100
Photo courtesy of  OneUp Components 

CNC work on the OneUp cog has some functional looking ramps, and the
overall craftsmanship looks above par against most of the competition.
The reasonably priced $100 42-tooth cog most closely matches with the
overall gearing spread of the SRAM 11-speed cassette, and I am looking
forward to trying one out when they’re available.


At OneUp Components we believe that every rider
should have access to the latest technology and that upgrading your
mountain bike shouldn’t cost you an entire paycheck.  We believe you
should work less and ride more!

We’ve made it possible to widen the range of your existing 10 speed
11-36 cassette.  No proprietary systems.  No need to replace half the
parts on your bike.  Just the extra range needed to lighten and simplify
your drive train.

Introducing the OneUp Components 42T sprocket.

CNC machined
from hard wearing 7075 aluminum, this sprocket fits behind most 11-36
cassettes, displacing one sprocket from the main cluster. The resulting
11-42 adapted cassette gives you 90% of the benefit of 1×11 systems at
10% of the cost.  Visit our compatibility page for more details.

 The OneUp Components 42T sprocket plays nice with 2×10 and fatbikes too.

 MSRP is $100 US and we will be shipping as early as mid January with free shipping worldwide.  E-mail with Grams Light Bikes in the subject line for a $15 discount code that’s good until Dec 18/13.  Visit our website – to get yours on order today.

 If you think we should all work less and ride more “Like” us on Facebook and repost this article.

running 9 speed?  Now that the industry has gone 1×11 crazy you can
find 10 speed components heavily discounted. Look around and you should
be able to upgrade to a wide range 1X10 drivetrain for as little as
$250! (Includes OneUp 42T Sprocket + shifter, rear derailleur and chain)

{ 2 comments… read them below or add one }

Anonymous May 1, 2014 at 4:03 am

Have you considered making an entire cassette?
Dave Freeman


Brian Mullin - Gram and Pastajet May 1, 2014 at 4:07 pm

Absolute Black from the UK is making a 4-cog cluster (28-40), but no full ones as yet.


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