The Camshaft
The valve timing between 49 state and California CBR600 motorcycles differ greatly.
They are as follows:
49 State:
Intake opens: 15 degrees BTDC
Intake closes: 35 degrees ATDC
Exhaust opens:  38 degrees BBDC
Exhaust closes:  7 degrees ATDC
California:
Intake opens: -5 degrees BTDC
Intake closes: 40 degrees ABDC
Exhaust opens:  40 degrees BBDC
Exhaust closes:  -10 degrees ATDC
The Carburetor:
The carburetor can be rejetted or just swapped.Swapping out the CA carb for a 49 state carb makes the most sense as the
CA carbs have extra vent tubes that must be blocked.
49 State:
Carb model #VP41A
Main Jet: 135
Idle Speed: 1,200 rpm
Pilot Screw: 2 1/8 turns
California:
Carb model #VP42A
Main Jet: 132
Idle Speed: 1,400 rpm
Pilot Screw: 2 3/4 turns
The slow jet and float level in both models are the same.