This page is a dynamic tool that will show you the stack/reach of Alpha One on YOUR particular bike. This Guide can help you replicate your current bike position on Alpha One, or set up a new bike with Alpha One based on numbers from a bike fitter. This Guide contains a database of the stack/reach numbers for most modern triathlon bicycle frames, as well as the actual stack/reach numbers for Alpha One. The Guide combines these numbers to produce a chart of actual X/Y coordinates of your 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. The steps below provide an easy-to-follow system for making sure you have the perfect fit with Alpha One aerobar.

Step 1: Determine your current fit numbers Show instructions »

Measuring Stack/Reach

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: Select your bike

Use the form below to pick your bike model. If your bike isn't in the list, you can input the frame geometry directly in the "Stack" and "Reach" fields. If you leave these blank, the fit chart will show the stack/reach information for Alpha One alone.

Step 3: Find your position on the chart Show instructions »