Using --no-rdoc and --no-ri with bundler
Bundler doesn't include rdoc and ri. There is nothing you need to do.
Make a file ~/.gemrc and put this in it:
gem: --no-rdoc --no-ri
That should make it apply whenever you run the gem command. (Even from bundle install)
See https://stackoverflow.com/a/7662245/109618 for a better ~/.gemrc:
install: --no-rdoc --no-ri update: --no-rdoc --no-ri