Thanks everyone for the responses.
For those discussing
frame size and fit of the bike, the only geometry that affects the saddle-to-pedal distance is the seat tube angle, seatposts with setback, moving saddle on saddle rails, and crank length (if you dare mess with that).
Unfortunately bike manufacturers
don't make several versions of a bike model with different seat tube angles. While at the same time humans do come in multiple versions of femur-to-leg ratio, which is primarily what determines what effective seat tube angle is needed in order to get the knee over the pedal -- in whatever knee position you determine is correct for you.
For those discussing
KOPS, my required saddle position has been determined by the fact that if I sit normally on the saddle my knees feel obviously cramped, and if I slide 2 inches off the back of the saddle my knees feel great. The great-feeling position coincidentally -- I later discovered, double-blind scientific experiment -- is KOPS.
Regarding
Cobb saddles: thanks for the suggestion. Too expensive and too race for me -- this is an upright comfort bike.
Regarding
Brompton Saddle Adapter Pin: this seems to be the one (quasi-) "respectable" option manufactured currently for greater than 40mm setback -- and it's ugly and scary and not actually available on the Brompton site as if they've been snapping and are discontinued?? There is a third-party site that has them. Considering it.
There are also skanky BMX seatposts with extreme setback:
http://www.bikeforums.net/showthread...1#post15216797
Originally Posted by
rdtompki
If you're light you might be able to get away with some sort of kludge, but if you're heavier you'll be putting an enormous stress on the seat post and the seat clamps
Yes in general I'm scared of too much setback of any kind, and am probably going to return this new bike and try to get one with slacker seat tube angle -- but I'm already on 72º and need a 67º seat tube angle (to move seat back 2 inches). And that's sooo easy to find
