User:Uipko

About me

I'm a software engineer, mainly developing webapplications with Java and python ;). I'm living in the Netherlands in a village near The Hague. My recumbent history is as follows:

• Started with a flevo bike (2005)
• After a year or two I wanted to have more exercise so I decided to buy a Rowing bike (2007)
• Instead of the flevo bike I'm now riding a Optima condor (2008).
• The Optima condor is replaced with a M5 shockproof 559 (2009-02).

I don't own a python (yet) but I'm thinking about building one.

Plans for building a python

I'm following the python mailing list form several years know. Now and then the plans to build an own python will come up. One big issue is that I never ever did weld anything. I think I just have to go for it, if it won't work i'll go for a composite bike. I would like to build a steel one first to try-out my design and be sure I like the way the bike handles. Steel and welding makes it easy to make adjustments. If the bike's does work as desired I'm planning to go for a carbon version. Ohh well we talking about plans for the next couple of years now ;)

Requirements

Below follows a list of requirements the bike should meet.

1. Same size wheels as big as possible with 82 cm inseam
2. BB-SEAT DIFF same as sp 559 around 15 a 20 cm
3. Not to low, bit lower as the sp 559
4. Suspended back wheel
5. Adjustable BB-EOS
6. Suitable for fat tyres 2"
7. Adjustable pivot angle

Design

The following list should cover the requirements mentioned in 2.1

1. 559 with 155 cranks, bigger is probably not realistic with a inseam of 82 cm
2. 15 cm on the sp559 it is around 17 cm
3. 43 cm, frame at same height as wheel axle plus mounting brackets
4. Rear fork same as flevo racer but with standard bicycle suspension
5. flevobike BB which slides over square tubing
6. Make sure front and back fork have enough space, test with kojak 2"
7. Use rod end bearings

I'm planning to use square tubing for the ease of use.

• rear fork same as flevo: 30*10*1.5 (stiff enough or should I go for 40*10*1.5)
  

other option is to reuse a 26" front fork from a donor bike this will make it easier but not so pretty

• front fork: 40*10*1.5 (30*10*1.5 not stiff enough according to other python builders)
• frame 40*40*1.5

--Uipko 19:48, 20 November 2007 (CET)