When does a speed limit sign take effect?

Usually when you pass the sign the new speed limit takes effect. The problem here is you were speeding either way. The good news is most speeding tickets are dismissed on procedural or evidentiary issues, not the facts. If you hire a good traffic ticket lawyer there is a great chance you can get the ticket amended to something that doesn;t get reported to your insurance or even dismissed altogether.

Generally, the speed limit sign takes effect upon your vehicle coming up next to it. Otherwise, if it was to become effective as soon as you could see it, that would become a major issue in every speeding case : when did the driver see the new speed limit sign? There would be no way to refute whether you saw the sign or not and from what distance. This way they make it a simple resoluation by saying it takes effect as you pass it. Good luck.