IMHO the pivot angle should be 70 degrees. The bike would then be easier
to ride at low speed and can be started from a dead stop without using
your hands. The concept that head tube angle is an important value for
good handling has been discredited.

See my files here
Single Track controls at:
http://home.earthlink.net/~wm.patterson/

and here

http://www.calpoly.edu/~wpatters/lords.html

I include a review of the handling qualities theory by David Gordon
Wilson. The author of "Human Power"

==========================

Wilson's comment on the Lords'
_____
Professor Bill Patterson has been enthusing generations of students
wanting to divert their over-abundance of human power into building and
pedaling helicopters and, mainly, bicycles. He has assembled his advice
on designing bicycles of all types (including motor-cycles) into a
cheerful and copiously illustrated volume that has become something of a
classic: "The Lords of the Chainring". It is now in its third edition.
The emphasis is on steering design for stability and responsiveness.
You will find Bill's advice, given in a few equations and graphs and in
many photographs, not only on what to do but on what not to do. It's a
delightful and instructive book.

David Gordon (Dave) Wilson
author, Bicycling Science, third edition.

==========================

I hope this gives incentive to try better geometry's for future front
drive bikes. When our bikes handle better, more people will ride them.

Bill Patterson "Chinkara rider"


Tim Karle wrote:
>
>
> Still doing rough sketches of ideas for my Flavo (20/20) build. Not
> going to have it separate at the pivot. Instead, maybe have the rear
> swingarm fold up underneath the bike coming up alongside the front
> wheel. Also have the seat and part of its rear brace `unlock' and fold
> forward to sit flat above the main tube. Just as a Bike Friday is
> designed. http://www.bikefriday.com/ <http://www.bikefriday.com/>
> Yet another geometry question. The FlavoFanClub site says the rough
> plans of the 20/20 are of historical value only because of `technical
> imperfections' and the bike has been completely changed. Side by side
> pics of an 80s, 90s and 2000+ models don't seem to show any difference
> in the basic frame geometry.
> I ask because the plans show the steering pivot to be 45º. However
> the geometry page on the Python site http://www.python-
> lowracer.de/geometry.html says that a Flavobike's steering pivot is
> 40º. Is this what's changed or is Jürgen wrong? Asking those truly in
> the know, which is correct on the latest model?
>

--
Some thoughts on Apache helicopter avionics
http://home.earthlink.net/~wm.patterson/helicopterthoughts/
http://home.earthlink.net/~wm.patterson/helicopterthoughts/id17.html
http://home.earthlink.net/~wm.patterson/helicopterthoughts/id16.html

See bikes and the first human powered helicopter at:
http://www.calpoly.edu/~wpatters/
Single Track controls at:
http://home.earthlink.net/~wm.patterson/

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