The first project we found is the E-cumbent by [Matt Shumaker] . [Shumaker]‘s ongoing project uses a power unit he constructed out of RC airplane electronics: the motor, the controller, a servo tester, and a battery eliminator circuit connected to 14 lithium polymer cells plus several CNC milled parts. The power drive connects to a sprocket mounted on the left side of the rear wheel. The bike is constructed with two reduction stages; the second stage has a freewheel that allows the rider to pedal while the motor idles, use the motor and pedal power combined, or use motor power alone. [Shumaker] also built a display console onto the handlebars, which shows trip information, MPH, and information on battery usage.

[Warren Beauchamp] designed a somewhat more simple electric recumbent he calls the Cuda-E. This design uses a 450 watt motor from a Mongoose pedal/electric motocross bike. It doesn’t just take the motor, though: it uses the entire rear subframe. The recumbent uses the motocross bike’s single pivot rear suspension, which attaches the rear and front subframes with a pivot and and a shock absorber. The motor is powered by a 24V lithium phosphate battery pack, but like the last project, [Beauchamp]‘s recumbent can use any combination of pedaling and motor power.

A third project we found is by [Dana Barlow], and it really whet our appetite for more detail. [Barlow] chose to use parts from the same kind of motocross bike [Beauchamp] did, but unlike him, [Barlow] did not leave the motor in its original place on the rear subframe. Instead, he moved it to just above the freewheel, freeing up the space for a larger wheel to be used. [Barlow]‘s bike is also distinct from the last two in that it uses remote steering: the handlebars and the suspension fork are on two different shafts. Unfortunately, very little information on the process was in the write-up.

All of these projects were found on Recumbents.com, which is a great one-stop resource for information on buying, building, riding, and racing recumbent bicycles.