I searched this forum and see where a ton of people rejet their bikes, but they all seem to have a slip-on muffler. I don't have any intentions of replacing the muffler (have to keep it quiet), but am curious if re-jetting will help. I looked at the service manual and noticed the AU bike has more power. I see a few differences in jet's and needles between the US and AU specs. Can I just up the main jet to #132, or do I need to replace the needle and starter jet along with the main like the AU bikes have different?

Thanks!
Scott

 

Yes. Should work fine. Mine came with a #132 main and #35 pilot from the factory. See how that goes. You may get away with raising the stock needle with a shim to squeeze a little bit more power if you fit an after market filter like a Twin Air.
Mine ran perfectly when new and completely stock.
You'll need to adjust the fuel screw too BTW.

 

I still have the stock exhaust system on my 09 and here is what I've done. Removed the airbox snorkel, 122 main jet, N1TC needle third grove, drilled slide vacuum port to 7/64", removed Welch plug and backed idle mixture screw out 2.5 turns. So rejetting with the stock pipe does help some.There is a noticable improvement but nothing dramatic. The 13 tooth CS sprocket and tires (Pirelli mt-21) have made the most difference in performance.