as promised in my last instructable, here's my attempt to build a 2-wheeler. why? i got infected by the bike-building virus. especially cargo bikes are just awesome vehicles: you meet lots of new people ("hey, what's this?"), you can transport nearly everything you need on a regular basis and it's better than a car if you live in a city like me (no parking fees, no searching for space to park a car, no insurances, taxes, gasoline, healthier & better for the environment,...). so go on and build your own, it's not that hard ;-)
Step 1: Donor frames
(sorry no pic) i got myself two donor frames from the local dump: an old 26'' mountainbike (hardtail) and a 20'' kids bike. the kids bike is just needed for the front fork and wheel, so if you find one where everything else is rusty and broken - take it! the other bike is used as a whole.
Step 2: Bulding the frame pt.I
after disassembling the bikes completely i took the bigger one and welded two tubes (construction steel, 34x2mm) to it as shown in the picture.
Step 3: Frame construction
now it's time to decide how long your bike should be. after that i suggest to draw the front construction 1:1 on some paper and put the rear part beneath it. it helps a lot to see if everything fits together. after that use it to weld the pieces together.
some technical notes:
- be careful to have the main tube to the front parallel to the ground. this means to measure exactly as possible the dimensions of the front wheel and fork and the center of the back wheel (see drawing)
- for the steering angle of the front wheel i used 75°