Sorry, but I'm not really "getting it" with all these "I want more power out of my FZ6" post as of late...
Want more power...don't buy a 500cc FZ6 then. sheesh.
I have to ask how long people have even had their FZ6's before they start asking this question? Are they even winding it out and/or shifting properly? Are they riding the bike to it's full potential (probably not)? If it's too slow, then upgrade to something else. Sure you can eek out some extra horses with exhaust, airbox and sproket upgrades.
"Oh but I like the FZ6 though" - Well there is always a VFR, countless BMW's, FJR or the FZ1 if you want more power while maintaining a comfy ride.
It's like people wanting their VW Bug to run like a Ferarri, but they don't want the Ferarri....they jsut want the same power and looks....
The FZ6 is what it is. It's a mid range commuter/touring bike that is very capible for what it was designed to do. Take it or leave it.