Good find from one of our members... just use the following Username/Password and click "Logon"
This is BMW US's electronic parts catalog. Thought I'd post this 'cause I haven't seen this here yet and didn't know if you all knew about it.
BMW Motorrad USA eNewsletter
Under the "Optional Equipment+Accessories, Motorrad" section, check out diagrams:
77_0381 - HP Race Power Kit
77_0382 - Einzelteile Race Abgasanlage (Race Exhaust System Parts)
Probably the Akra full system