Sigma X Stem
  • Sigma X
    Carbon Aero Stem

    Restocking Soon
  • Purchase Info (show) »

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  • Alpha X technology
    ported to a stem

  • Minimal frontal profile

  • Integrated centerpull
    cable routing

  • Manages cable with
    bolt-on cover

  • Integrated BTA
    bottle mounting

  • 25mm stack,
    100m reach

Sigma X: The Superstem

When we first introduced the original Sigma, it was a revolution - the first stem on the market with integrated cable management. Since then it's been imitated by many others, but never surpassed ... until now. The all-new carbon-fiber Sigma X is the next generation in clean stem design, borrowing all the new technology from our Alpha X aerobar, and porting it to an aero stem. It comes complete with our aero-matched stem spacers, ultra-low-stack dust cap, and more.

Industry Feedback

"How do you aerodynamically clean up the front end of a bike with a standard front end? There is really only one stem that accomplishes this, and it's the Sigma X. This stem turns standard-front-end tri bikes (and aero road bikes, for that matter) into virtual superbikes."
-Dan Empfield ,

"We liked the Sigma. We love the Sigma X. TriRig has a stem system that is sure to be a favorite in transition for a long time to come."
-Mike Longin ,

"As with the rest of TriRig's gear, the X-Series appears to be exceptionally well-thought out, surprisingly practical and features that all-important aero focus."
-Tom Ballard ,

"All in all, the new Sigma X stem is a refined solution for a part that many of us take for granted."
-Geoff Nenninger , Triathlete Magazine

New Features (See all)

All-Carbon Construction

The new Sigma X is MUCH lighter and MUCH stiffer than its predecessor, owing to all-carbon construction. Now you can have an aero advantage without a weight penalty.

Born from Alpha X

The aero features from Sigma X were borrowed from our brand new Alpha X aerobar platform. The aero-matched spacers are identical, as is the wedge-style steerer clamp, and the removable centerpull cable stop. The Sigma X is basically the Alpha X, minus the bar.

No Fork Trimming

The new Sigma X eliminates the traditional drawback of integrated stems, which is the requirement of trimming your fork's steerer tube. The Sigma X cable cover stops just in front of the steerer tube, allowing you to maintain clean cable routing and also preserve the ability to change position in the future.

Integrated BTA Mount

The two bolts on top that affix the Sigma X cable cover --- those are spaced at 63mm for a water bottle cage or storage box. So you get a clean mounting option, no zip ties required.

Read about all the new features in depth, right here » All Features.

Whether you're building up a new tri bike, or an aero road bike, The Sigma X is the perfect match for your bar. It even takes care of your hydration needs with an integrated BTA mount, right on top of the stem. And with integrated centerpull cable/housing management, and shifter cable management, it's the cleanest stem you'll ever see.