Although BikeCAD drawings in PDF form are by default full scale, these PDF's will often be printed onto smaller sheets. It's always nice to make full use of all the space on a given sheet, and that's why we'll want to choose the appropriate page aspect ratio in the Title block dialog box. Standard options include 8.5"x11", 11"x17" and ISO 216 for international standard paper sizes. In BikeCAD version 13, we now have the option to specify our own custom aspect ratio. Entering a value of 1 would give us a square drawing, Entering 4/3 works out to 1.3 repeating which gives us the rectangular drawing we have here.