See other failures under 000.html.
Race Face XY seatpost (30.9mm) failure at head.
From http://picasaweb.google.com/thisnthatntother/Fail?authkey=8ePsxVY29kw as of 2008/02.
Used on full-suspension mountain bike. Saddle kept far back and slipped even when tightened. Rider weight bout 80kgf.
See also FAIL-091.html.