How to disable a keybinding

[finalclass]

I have a keybing set for some custom function for <leader>or however this does not work in orgmode.
Even if I set the keybinding directly in an org file it's still not respected and the orgmode keybinding is used.
What can I do to disable this (and some other) orgmode keybindings?

[doak]

This works for me™.
How do you set the keybinding. I've just tried :map <leader>or :echo "doak"<cr>. If I press my configured leader key and then or "doak" is printed.
Perhaps the leader key had been overwritten by vim-orgmode in your case. Which one do you use? I am using the space key. (:echo "'".g:mapleader."'")