Pre 06 CA models had a cat & stainless Y. The pre 06 49 state did not. The cat equipped models also have a different ECU as far as I know. 06 & later all have a cat & stainless Y but I believe the CA models still have tougher emmisions to mett through the ECU.
They're also narrower so they can split-lanes easier on the freeway!
Temecula, CA (So Cal)
Too often we lose sight of life's simple pleasures.
Remember when someone annoys you, that it takes 42 muscles in your face to frown ...
But it only takes 4 muscles to extend your arm and bitch-slap that mother- upside the head...
I have an 07 cbr600rr with a cat. It's the cleanest motorcycle exhaust I have ever seen. No soot, no smell, no nothing. I love it. I wouldn't dream of changing it. Yeah, I could change the exhaust and put a PC on it and get another 5 HP. It runs perfectly as is. I'd rather not have the smell.
Honda does cat converters better than anyone. I'd leave it in.