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Recumbent Sizing Guide (X-Seam)

At, we like to use the X-Seam Measurement to fit riders on recumbent trikes and inseam to fit riders on upright trikes (like the sun traditional).

We use this measurement to adjust your trike to fit you out of the box, but it's simple to adjust your trike later to suit your preferences. This is just a rough measurement to make things easier for you.

You can see how to take your measurement in our video.

Or you can read about how to measure it in-depth here:

To measure your X-seam, you'll need a tape measure, a sturdy board (like a piece of plywood or an ironing board), and an assistant to help you. If you currently ride a recumbent bike, you can use that to take the measurement instead of the board.

How to find your x-seam measurement


Start by placing the board against a wall at 60*. You can use a protractor (or print this one out) to measure the angle, or measure the length of your board, divide that length by two and place the end of the board that distance from the wall. For example, a 36" long board will be placed 18" away from the wall to get a 60° angle.

Measure the length from the end of the board to the end of your feet, and this is your X-Seam.

If you're having trouble with the measurement or want to size your bike a different way, feel free to choose "I'm not sure" from the drop-down menu, and we can discuss your needs after you place your order.