My question would be: How do they work. If they take a picture of the front of your bike, you're not going to have a license plate on the front, and a full face helmet obscures your face. How would you get a ticket?
If it took a picture after you passed, it could get your plate. On the other hand, if you saw a unit, couldn't you just stop and wait for another car to pass?
If it took a picture after you passed, it could get your plate. On the other hand, if you saw a unit, couldn't you just stop and wait for another car to pass?