Simon Brooke wrote:

It's much more springy than aluminium and IME a bit more springy than
steel.

But simply /along/ a tube (i.e., down a seatpost) the value of "more"
will be somewhere between negligible and bugger all, I'd have thought.
I think you'll need lateral spars somewhere for any degree of
appreciable flex, and a seatpost will be effectively a rigid bar made
from any of the above.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
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