Reducing drag can increase top speed, but I doubt adding *that* wind deflector would outperform simply making yourself small by tucking your head and torso.
Regarding emissions, the USA and Thailand have less strict motorcycle emissions requirements than Europe and countries that use the Euro standard such as Japan, but as far as I can tell Australian Design Rules don't yet have noxious emissions requirements for motorcycles. Correct me if I'm wrong there, but it makes sense considering Aussies get new road-legal 2-stroke Enduros.... Yeah, I'm jealous. Most ECMs have region specific part numbers which could enable a different tune for each region. I wouldn't be surprised if the Australian model does have a different tune and makes more power. I also wouldn't be surprised if the USA model has a tune that makes less power than the Japanese model even though Japan has stricter emissions... the USA sometimes gets hosed on vehicles like that.