I couldn't find handle bars in the shape I needed for under-seat steering, so I made some from 3/4" EMT conduit. I liked the looks of the "steer-horn" or grip-forward design on some of the trikes out there, so I came up with a way to bend the shapes. The basic approach was to make two mirror-image halves and join them together. It takes a tube cutter, a ¾” conduit bender, a large square and a marking pen. A diagram at the end shows the two sizes I made for my Quadster.

The measurement marks are for aligning the start of a bend, not the middle. You work from left to right, keeping the tube bender on the right side of the mark. For some basics on conduit bending in general, these sites were helpful: http://www.elliottelectric.com/Refer...ing_guide.aspx , and http://www.mikeholt.com/documents/fr...ndRaceways.pdf.

Cut two pieces of tube 30” long. Measure and mark the tubes - the example pictured here has marks at 5”, 10”, 15” and 22”. The shortest section you can practically bend is about 5”. Then make lines lengthwise on the centerline through the first two marks, using the straight edge of the square. These are for aligning in the bender.