X-Seam Measurement

Wear shoes you would typically use for riding. Sit very tight against the bottom of the board, lean back, and stretch your legs out straight with the soles of your shoes perpendicular to the floor. Measure the distance in inches from the front of board to the bottom of your shoe. This is an important measurement so have an assistant help you get an accurate number.  Use an ironing board, a piece of plywood or whatever you can find. Lean it against a wall at the recommended angle or as close to it as you can eyeball.

Click to enlarge.

The Access, Sport, Race and Zoomer products have a sliding boom tube so one size fits all per the chart below. The Edge has a fixed boom that is not detachable. The Path, Cruiser, Tour, and Tandem have detachable boom tubes of different lengths but they are not a sliding adjustable piece. The boom tube is the front part of the frame that holds the bottom bracket, crankset and pedals. It attaches to the frame where the outrigger tubes meet the main tube(or where the arms of the frame meet the body).

The boom tube length guidelines listed below are merely suggestions, this is by no means an exact science.  For those of you who are on the fence, here are some guidelines.  If you're the serious racing type who likes to recline the seat all the way back and go fast, add an inch to your x-seam measurement.  If you're more inclined (no pun) to sit very upright and just cruise around town and be cool, you might need to subtract an inch. Also, if you're ordering a Path, Cruiser, or Tour and you're in-between sizes, you may want to order a spacer. The spacer lengthens the boom tube one inch which is half of the typical two inch difference between boom sizes. The spacer works great for those riders who measure in the middle of two sizes. It also provides more crossbar clearance for riders with very long feet.