I started working with a group that wanted to move some boxes of veggies around town with pedal power. We searched all over the Web for ideas about what to build and ended up with the general plan you see here.
We had access to lots of donor bike parts from a local alternative transportation group. Follow the link below to see how you can get similar parts.http://www.instructables.com/id/How-I-Get-Free-Bike-Parts-Legally/
This Ible describes the prototype for the cargo trike that followed. I am working on an Ible describing the next version of the cargo trike we have built. I will add a link to that Ible when I get it published.
Prototype Cargo Trike Specifications:
Overall weight 75#
Cargo portion with front wheels 48#
Rear portion with rear wheel 27#
Cargo Bed 30" X 48"
Pivot Pin 24" from front
Front wheel axles 27" from front
Handlebar is 30" above the bed