On 28.11.2007 16:50, Kevin Bailey wrote: > I had assumed that PSI was dependent on the ratio between the > pedal "width" (distance from the center of the pedal to the > centerline of the bike) and the BB to pivot distance. Basically, > that PSI was caused by the sideways component of the pedaller's > stroke (which attempts to turn the wheel) and corrected by the > foward component of his stroke (which attempts to straighten the > wheel.) This ratio is equivalent to that between the pedal width > and the BB to pivot distance. Put plainly, the further back you > move the pivot (without changing the pedal width), the less the > PSI. I assumed this was why the Python was better in this > respect than the Traylor/Cruzbike designs. Hello Kevin,I thought this too - until I built the PX.5, an experimental prototype where the pivot was moved 25 cm further back than the normal position:
http://python-lowracer.de/pics/Python%20PX.5.jpg PSI was clearly noticeable and the bike was hardly rideable. Cheers, Jürgen. ============================================================ This is the Python Mailinglist //www.freelists.org/list/python Listmaster: Jürgen Mages jmages@xxxxxxTo unsubscribe send an empty mail to python-request@xxxxxxxxxxxxx
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