Hello all,
Reading Bjørn & Jürgen's discussion of inseams, I realized that I forgot that my inseam is 5 cm too short and started thinking that it was only 5 mm too short!
So forget my amazing plan. The absolute maximum I could shorten the distance between the steering BB and the FWaP is 2 cm. As per "The absolute minimum distance [between BB and FWaP], I would recommend is 40 cm (84 cm inseam)." (from http://www.python.tieflieger.net/construction.html ), I could shorter the front 2 cm as well, although using the absolute minimum seems like a bad idea.
So let's assume I shorten the distance between the steering BB and the FWaP by 1 cm, and I also shorten the distance between BB and FWaP by 1 cm. Then my 81 cm inseam 'becomes' an 83 cm inseam. I can't reduce the BB<-->FWaP anymore without causing problems, so I need to reduce the SBB<-->FWaP by 3 cm (in addition to the 1 cm reduction), which means reducing the outer diameter of the tires by 6 cm. Hmm, although reducing the tire diameter will also reduce it's width, reducing interference between the sides of the tires and the 40x10 tubes, so it should be possible to reduce the SBB<-->FWaP by 3 cm (in addition to the 1 cm reduction) without having to reduce the tire diameter by a full 6 cm.
Another option is to redesign the SBB<-->FWaP connection to something more like the letter "U" (bottom of the "U" is the SBB, sides are the 40x10 tubes) then the letter "A" (top of the "A" is the SBB, "A" cross bar is the cross member, sides are the 40x10 tubes), so that the tire could sit much closer to the SBB axis. It looks like it could be reduced by a good 4 cm or so (total), so if I reduce the SBB<-->FWaP by 4 cm total (from 38 cm to 34 cm) and I reduce the BB<-->FWaP by 1 cm (from 42 cm to 41 cm), then my 81 cm inseam should be a perfect fit with everything else standard (44-559 tires, etc).
Michael
PS: I found an oxygen tank to complete my oxy-acetylene setup! I'm getting closer and closer! Plus, the face shield and the gloves are more like optional accessories than essentials, right? (Just kidding!)
