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TriRig Sigma

  • Sigma XF

  • Sigma N35

  • Sigma XF

  • Sigma N35

  • Centerpull cable routing
    Recessed under-mount bolts

  • Integrated BTA mount

  • Di2 window

  • Ultra small frontal area
  • Sigma XF

  • Sigma N35

At long last, our new and improved Sigma stems are available! The Sigma XF (flat) and Sigma N35 (+35mm) are each machined from solid blocks of T6-7075 aluminum for rock-solid durability and fatigue life.

The TriRig Sigma is the first stem produced just for triathletes, and has been designed with aerodynamic performance as the primary focus. The first thing you notice about the stem is that it adds almost no frontal area to your rig, reducing drag. The stem also has a number of unique features designed to make your rig faster, cleaner, and more beautiful:

  • Internal cable routing via a removeable fairing
  • Internal cable stop for use with centerpull brakes like the TriRig Omega
  • Recessed bolts throughout - not one millimeter of any bolt is exposed to the wind, to promote smoother airflow and reduce drag.
  • Handlebar bolts tighten from underneath the stem, to facilitate easier adjustment or disassembly for packing.
  • Fact that stem cover bolts on after cables are routed mean no fishing through the stem to route the cables. Simply route as normal, then tuck them in and bolt the cover into place.
  • Included shim allows use with 1-1/8" or 1" fork steerer tubes.
  • Includes BTA mount for attaching a bottle cage directly to the Sigma.
  • Available in 90mm lengths, in 0mm rise or 35mm rise.
  • Please refer to the Installation Guide for lots of details on the technical specifications of the Sigma.

You can view a detailed gallery of images as well as a more thorough explanation of the Sigma in this article.