For the archives:
Here are some resources for Cannondale tandem owners that will help them understand how to adjust their eccentric bottom brackets and, should they ever become "stuck", how to get them "unstuck":
This first link will take you to Cannondale's eccentric supplement. It's pretty clear-cut and the methods as described work well unless the wedge becomes stuck to the point where hammering away on the wedge bolt has no effect:
http://www.cannondale.com/asset/iu_f...plement_en.pdf
FWIW, here's a link to the Cannondale Tandem supplement as well:
http://www.cannondale.com/asset/iu_f...plement_en.pdf
Both of these files can be found on Cannondales Web site Tech support pages:
http://www.cannondale.com/tech_cente...ther_bike.html
If you find your Cannondale's eccentric's wedge will not release, you'll want to follow these instructions for "extracting" it. This is the only, sure-fire way to get it undone with minimal fuss and reliable results:
http://hobbes.ucsd.edu/tandem/Maintenance.faq