I deal with similar leans, and find it's more pronounced on a hard firm
seat, less so on padded or air seats. I believe it's due to my pelvis
being tilted so that the right side is lower than the left, and the
softer seats absorb the misalignment and mask it a bit. I have more
trouble keeping a stable posture on the harder seats.

Some years ago a physical therapist did measurements which showed that,
while lying flat on my back, the right foot was two inches farther down
the mat than the left foot: all due to the tilt of the pelvis. I'm
thinking that if I can reduce this misalignment my posture will be
easier to maintain.


--
idiorythmic
------------------------------------------------------------------------
idiorythmic's Profile: http://www.unicyclist.com/profile/12653
View this thread: http://www.unicyclist.com/thread/54405