Many cities use timer sequenced lights if the road is major enough. It took a little bit of understanding and trial to find out that even though my city's speed limit is 25mph, the lights are all green at 19-22mph. If you get off pattern and have to sit there are no sensors and delay is around 2-3 minutes each. There is one where it is off pattern no matter what, and it works out to be a jump or a long wait. If there are cars in line with me I will usually wait with them, but if the road is empty I will look and then go. In legaleese it is called a "defective" light because the modern design sensors are required to sense metalic bikes.