Originally Posted by
Kimmo
Yep. Modern cogs are designed to sit next to the cogs you buy them with.
exactly, you'd have to replace the 14-tooth cog with another 14-tooth that was designed for use next to an 11-tooth.
As usual, Sheldon tells all, his article deals with Shimano ones rather than Campy, but the basic problem and solution should be the same
http://www.sheldonbrown.com/k7.html (read the bit about custom cassettes, there's a link at the top of the article)
As for it not actually working at all, I've been running a cobbled-together cassette on an MTB for a while, some of the cogs are not designed to work with the ones they're next to, so they do shift rather badly, but it works.