As far as I understand in CA you don't even legally need turn signals.
Incorrect. The CAVC requires that motorcycles built after, I think, 1/1/74 to have turn signals amber or red in color. They have never been hassled because most traffic "enforcement" in CA is really revenue generation. They go for the easy high dollar picks like speeding and rolling stop signs/lights.
<rant>Personally, I can't stand those friggin morons that move their brake light to up to the left side foot peg and rip off their signals or pull their signals and make one side of their tail light blink. The ones that bug me the most are the people that hand signal cause they think it's cool, but can't even be bother to lift their friggin arms up so that some one can see that they are actually using hand signals.</rant>
Here's a no joke story that should scare the **** out of anyone. I was waiting my turn at the DMV to take my motorcycle test and watching the cage people in front of me.
The people two cars in front of me didn't understand why the examiner wouldn't let them take the road test because even though one brakelight didn't work, the other side and the CHMSL light still worked. Idiots.
Then the lady in the car in front of me got off to a rousing start. The examiner asked her to make a hand signal for a left turn, she correctly stuck her left arm straight out. Then he asked her to signal for a right turn, she stuck her *right* arm straight out. English wasn't her first language so he asked her to do it again, perhaps giving her the benefit of mis-understanding or being nervous, and she did it again. Scary. As I was getting my license finalized ( of course I passed

) I heard the examiner coming in telling the woman that she didn't pass.