Like I said you can make ANY ENGINE FASTER. how much money do you want to spend.
as for honda, they're worried more about RELIABILITY, emissions laws, noise laws, LAWSUITS, WARRANTIES... not saying that their engineers aren't worried about performance. just that it's just a Piece of the puzzle for them.
the basics of making power have been around since the internal combustion engine itself. if you want to make power, just putting a pipe on ain't gonna cut it. Gotta MATCH PARTS. CAM TO INTAKE TO CARB TO PIPE TO BREATHER, ECT...
like you said, check out what you have before you go messing around with.
It's like martial arts, just because you know how to break boards doesn't make you a black belt. it's just PART of the big picture. you have to work on ALL OF THE BIKE to make it faster... and remember that to make it faster, you may be trading off, reliability, takeoff, quietness,idle quality... so is it worth it?