Hi millisami,
First you need to install Speedy with "sudo" command. If not, Speedy
binary will not copy to the bin folder. You can only run "speedy" if
you have the binary.
If RVM doesn't allows to install gems with "sudo", try this method.
1. Type "sudo su" and give the password. Now your shell will run in
the privileged mode.
2. Now you can install Speedy with "sudo". Just type "gem install
speedy". - Since the shell already authenticated, necessary binaries
will copied to the necessary folders.
3. Now you can use "sudo speedy config-passenger"