Alpha - Installation Guide

Alpha One Installation Guide

Setup Notes

  • Please refer to all part names indicated in the image above. These will be referenced throughout this Installation Guide.
  • All bolts on Alpha One can be adjusted with a single 4mm hex wrench. We include a high-quality Silca 4mm wrench for easy on-the-fly adjustments. However, always use a torque wrench for initial installation, and whenever available. Overtorque can result in damage to the bar, not covered by warranty. However, the Silca wrench provided is a small one, unlikely to overtorque, and ideal for temporary on-the-road adjustments.
  • Alpha One can accept any 22.2mm standard aerobar extension. It can be purchased with our own TriRig Gamma extensions which allow a variety of different positions to be achieved. However, it can also be purchased without any extensions so that you can use your own. Any standard extension may be used. Some older extensions use a 22.0mm diameter instead of the more common 22.2mm standard. These undersized extensions may be difficult to tighten down, and we cannot guarantee fit. However, we have successfully tested some 22.0mm extensions in the bar, and they fit well. So if you have a favorite extension in the 22.0mm standard, there's a good chance it will work in Alpha One.

Stem Hardware

  • Begin by removing the headset cap and any round spacers already on your fork. Alpha One is designed with aero-matched stem spacers and integrated dust cap for superior aerodynamic performance. The bottom surface of the base bar, and the aero-matched stem spacers all feature a 1.5mm counterbore to cover your headset, eliminating the need for a dust cover. However, if your particular setup requires its existing dust cover, or the Alpha One system does not adequately cover your headset, you can use the 1.5mm-thick Headset Spacer and use your existing dust cover. This part goes underneath your lowest stem spacer, or directly beneath the base bar if you are not using any stem spacers.
  • Alpha One includes in integrated cable cover which requires you to trim your fork steerer. It can be used without this cable cover if you wish to keep spacers above your stem. However, for best aerodynamic and functional performance, you will want to trim your steerer tube and use the integrated cover. Trim your steerer tube so that it ends 2-3mm below the top surface of the Alpha One's integrated stem.
  • With the cable cover removed, install Alpha One onto your fork as you would any other stem. Apply carbon paste around the steerer tube, and all interior surfaces of Alpha One stem clamping zone. Install the integrated cable cover, and follow the torque specification of your headset for the headset preload bolt (in general, just enough torque to remove any play from the steerer column). Then use 5-6 Nm of torque on the stem pinch bolts to tighten Alpha One to your steerer tube.
  • Alpha One features advanced cable routing for use with any drivetrain, as well as centerpull brakes like the TriRig Omega X. The brake routing system features a removable cable stop so that you can either run bare cable to your brake with the stop in place, or run full housing or a hydraulic line by removing the cable stop.

Extension + Arm Cup Hardware

  • Attach the Dragonfly to the Monopost, using the two M6 countersunk screws and the special Tilt Washer, with the Tilt Washer's arrow pointing forward toward the bicycle's front wheel. The angle of tilt is indicated by the hashmarks on the Monopost, and can be adjusted from approximately -10 to +17.5 degrees. Tighten both M6 countersunk screws to 8 Nm. The tilt angle can be adjusted or readjusted at any time, even with the arm cups in their narrowest position.
  • Alpha One's Monopost allows for continuous stack adjustment. Adjust the stack height according to the Fit Guide and tighten the front set screw to 8-9 Nm. This adjustment can be changed at any time.
  • Finally, slip the extensions into the Extension Clamps and tighten the two M4 screws to a torque of 4 Nm. Note that this is relatively low torque compared to many other aerobars. As with all bolts on the bar, we designed Alpha One Extension Clamps to provide a stable, secure grip without the need for unnecessarily high torque.
  • Mount the arm cups via two M6 x 12mm bolts each. Note that although there are four bolts on the Dragonfly cup mount, only TWO are meant to be used at any time, as shown in the images below. This allows seven distinct pad stance width positions, and three pad reach positions. Note that in every pad position, you can access the Arm Cup bolts, Extension Clamp bolts, and Tilt bolts, at any time. There is ZERO bolt occlusion on Alpha One, meaning that all bolts are accessible at all times, and are never covered up by other pieces of hardware. This is true no matter how you have set up your bar.

Mechanical Cable Routing

  • In general, cable routing is straightforward and self-explanatory. However, for mechanical cables, it can be helpful to leave the cables routed outside the extensions, in order to maximize your ability to make stack adjustments without needing to make any changes to the cable routing. Have a look at the images below to see our recommended method for the routing of mechanical shifter cables.

Remove cable cover, route cables.

Collect cables and align underneath cable cover

Replace cable cover

Final result

Housing outside extensions

Minimal frontal area, maximum adjustability

Alpha One Measurements:

Pads in rearward position

Pads in centered position

Pads in forward position

Pad stance width

Bar width is 400mm c-c

Arm cup specs

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.