Farmhack has complete instructions for making a bicycle powered thresher. It works on various crops including dry beans, wheat, rice, rye, einkorn, and lupine, and threshes about one pound per minute.
This is the first of three tools for small scale grain processing. The other two tools are the bicycle powered fanning mill and the bicycle powered de-huller/flour mill.
Unlike some “hacks” for small farmers, the Grain Bikes don’t solve an acknowledged problem so much as create new opportunities for small farmers. Dry beans and grains are non-perishable, can be sold, eaten, or planted to avoid seed costs (such as rye for cover crops), and, the labor for processing them can be shunted to the winter when more time is available.