PPP is the abrieviation both for PollyPupsPueppchen and PetersPythonProject.
The two constructing paradigms of the PPP are:
1. using as much parts of old bikes as possible and available,
2. using screws instead of welding.
The reasons are: low manual skills, no adequate tools, no workshop.
I'm very nervous in traffic situations, so I can't use this bike in a normal way (but I'm working on this). From my experience, the most important factors, that influence the "ride-ability" of the python are trail (it should not be much less then -20cm) and pivot angel. I wasn't really able to control the bike until I corrected the pivot angel (from 67,5° to 66° - not much, but it had the effect, that the trail was increased from -28 to -22cm). Then, riding the bike was much easier! Next improvement: new seat! Great!!
More photos and videos on http://home.arcor.de/-peter-wenzel-/pommesclub/fahrradbau/ (I added some detailled pics of the screws, that hold the PPP togehter.) and http://www.youtube.com/user/pollypupspueppchen
Special thanks to: Peter F. for discussion and support (tools&materials), Carolin W. for emotional support, filming and taking photos, and the pythonaut-community for advices to improve the PPP!