Alpha - F.A.Q

Frequently Asked Questions

  • You say that Alpha One is faster than Alpha X. Is that really true? What about Alpha X's super-deep airfoils?

    • Yes, Alpha One is genuinely faster. Not by much. Our CFD studies show it to be about 7-8g faster on average (across a variety of stack heights and setups). This translates to a savings of about 1 Watt. In the wind tunnel, it is very difficult to detect a difference that small, reliably. It takes good CFD to really test differences this small. Alpha One vs Alpha X might look like a wash in the wind tunnel. Our goal with Alpha One wasn't to make a significant aero savings, as Alpha X is already a VERY fast bar. Our goal was simply not to make Alpha One slower than its predecessors, so that it wouldn't be a compromise to utilize its exceptionally-flexible fit system. And we succeeded. It's consistently faster than Alpha X in all the configurations we tested. The reason we were able to get away with a shorter airfoil section on the base bar wing is not a simple story to tell. Suffice it to say, we tried a LOT of shapes for the aerobar wing. Some were very deep, more like Alpha X. Yet the deeper wing sections did not make a faster complete bar. There are lots of little interactions where the wing meets the stem, transitions into the top and sides of the stem and Monopost, etc. The shallower 3-to-1 sections worked better at preventing those little interactions from getting messy and creating drag on this particular system.

  • I want to purchase the Omni bike, with the Alpha One bar. How can I do that?

    • When you purchase your Complete Omni Frameset, it now comes with Alpha One by default.

  • How are cables routed on the Alpha One? Can I hide my Di2 junction box in the cavity?

    • Cable routing through Alpha One is easy, straightforward, and hides cables from the wind. The brake cables route internally through the wing. The front brake cable exits the opening at the bottom of the bar, and you can route full housing or hydraulic line through the hole, or route bare cable via the included removable cable stop. The rear brake cable exits the back of the bar under the cable cover. Shifter cables or wires exit your extensions, and enter the stem cavity. They are then hidden under the cable cover, by entering the cable port just behind the Monopost. You can route all your cables and then hide them, rather than have to execute a convoluted routing operation with the cover already in place. The images below show routing with Shimano Di2 wires, and full brake housing. And yes, the 5-port Di2 junction does fit in the stem cavity. It's a tight fit, but it works. The routing would be the same for mechanical cables, except that the shifter cables would not be taped to the back of the Monopost, instead taking a slacker route to the cable port behind the Monopost.

Cables and wires route into the stem cavity

The 5-port Di2 junction fits snugly inside

All cables, wires, and junctions tucked inside the stem

Di2 wires snugged up to the Monopost, for fully-hidden cables

Di2 wires snugged up to the Monopost, for fully-hidden cables

Di2 wires snugged up to the Monopost, for fully-hidden cables

Fit Guide

This Guide shows you how to set up your TriRig Omni with the TriRig Alpha One or Alpha X aerobars. This Guide can help you replicate your current bike position, or set up your bike based on numbers from a bike fitter. The Fit Chart below shows the actual X/Y coordinates of your arm pads measured from the bottom bracket. This coordinate is the most important number that bike fitters use to determine your position on a triathlon bike. Be aware that some fitters use a coordinate to the top/back of the pad, rather than the top/center. In that case, you can subtract 44mm from all of the reach numbers in the Fit Chart, which yields the back of pad number. The steps below provide an easy-to-follow system for making sure you have the perfect fit with your Omni.

Step 1: Determine your current fit numbers

What we want is the X/Y coordinate to the top/center of your aerobar pads, measured from the bottom bracket. Most bike fitters can provide this number to you when performing a bike fit (although some provide it to the top/back of the pads rather than top/center). If you already know these numbers, you can skip this step. Otherwise, follow the steps below to determine these numbers for your current bike setup:

1-Place your bicycle up against the corner of a room, with the back tire abutting the wall.

2-Next, measure the vertical distance from the floor to the center of the bottom bracket. We'll call this measurement Floor Offset (FO).

3-Measure the horizontal distance from the wall to the center of the bottom bracket, we'll call this measurement Wall Offset (WO).

4-Measure the vertical distance from the floor to the top of your aerobar pads. This measurement will be Pads-To-Floor (PTF).

5-Measure the horizontal distance from the wall to the center of your aerobar pads. This will be called Pads-To-Wall (PTW).

6-Subtract Floor Offset from Pads-To-Floor (PTF minus FO). This is your Pad Stack.

7-Subtract Wall Offset from Pads-To-Wall (PTW minus WO). This is your Pad Reach.

Step 2: Review Frame Geometry

Small Medium Large
Frame Stack
(BB to Headset)		 490mm 525mm 560mm
Frame Reach
(BB to Headset)		 375mm 405mm 435mm
Front Center 560mm 600mm 640mm
Rear Center 400mm 400mm 400mm
Seat Angle 79° 79° 79°
Head Angle 72.5° 72.5° 72.5°
Fork Offset 48mm 48mm 48mm

Step 3: Select Size, then find your position on the chart

The chart below shows the stack and reach information for the TriRig Omni with the included Alpha X aerobar, complete with the number of extension spacers and stem spacers used for each setup. Here's how to use the chart:

1-Use the dropdown box in the upper-right corner of the chart to select a bike size.

2-Find your Stack in the left-hand column of the chart, or the row that most closely matches your stack. Every cell in this row represents a way to set up the Alpha X on your Omni that will produce this stack number.

3-Each cell states the amount of Pad Spacers as well as Stem Spacers to use in order to hit your stack number.

4-In most cases, there will be multiple cells that can hit your stack. The best setup for your position will generally be the one with additional colored cells above AND below your selected cell. These cells represent room to move up or down in the future, merely by adding or removing Pad Spacers, which is generally the easiest way to make a position change.

5-Cells in blue represent a standard setup with the extensions over the bar. Cells in green represent the special undermount position, where the extensions are mounted below the bar.

6-Once you have selected a cell from your Stack row that represents your preferred position, look at the bottom of that column to the Reach section. The three rows of Reach cells show the reach to the center of the pad based on the three different adjustment positions available on the Alpha X arm cups. Select the one that most closely matches your Pad Reach number, and set up your pads/cups accordingly.

7-Note that fit numbers for the Omni w/ Alpha X are measured from the top/center of the headset to the top/center of the pad. All measurements for overmount hardware include the integrated BTA mount.