Cut-Rate Recumbent Bike

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Once the axle assembly is fused together, contour the forward end of each frame rail (those twin tubes should first be temporarily clamped against two 3 7/8"-wide spacer blocks ... with the kickups parallel and pointing up) and join the pair to the center rear of the dropped tube. With this done, trim one end of the crank post, and weld that support to the front of the axle so it's raised 25 degrees from level (or is 10 inches off the table at its forward end).

After completing these steps, cut — and then fit — the radius rods in such a way that the front pair stretch between the crank post and the head tubes, and the rear set join the forward tips of the frame-rail kickups to the back of those same steering heads.

To make the two hoops at the rear of the chassis, merely bend your 1/2" E.M.T. to form two 4 1/4" and two 10 1/2" legs, all with 40 degree arcs ... then join each set together, using 1 1/2" lengths of the same conduit. The fender bracket is welded into the openings at the ends of the frame rails, after which the small hoop should be fastened to the upper surface of the rails, at a point 10 inches forward of the larger support. Finally, weld the dropouts (the flat plates that hold the rear axle in place) to the lower surface of the rail kickups ... positioning them 4 3/8 inches apart and flush with the ends of the rails.

At this point, complete the chassis itself by mounting the bottom bracket (the housing for the pedal-and-crank assembly) to the crank post. To do so, first determine whether that support is the proper length by "trying the frame on for size". If you (or the intended rider) have a problem reaching what would be full pedal extension when sitting on the frame rails at a point nine inches behind the axle, you'll have to Cut the crank post to size. You can also extend that stanchion slightly, if necessary.

(To protect the crank post against excessive flex, use the 14-gauge X 1" X 24" strap-steel section as an internal spine, by first cutting it to the same length as the support, then drilling a series of' 1/4" holes — about 4 inches apart and perpendicular to the axle — right through the tubular stanchion. When the strap is slipped down the center of the tube and its edges are welded to the walls at each opening, the post will better resist bending under leg pressure.)

The bottom bracket should be cut from one of your bike frames, and the rough edges should be ground flush to the housing. Then it can be welded squarely to the end of the crank post to support the pedal-and-crank assembly.

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