https://www.usatoday.com/news/nation/2008-0...ight-laws_N.htm
"The traffic lights in question are controlled by devices buried under the road that operate similar to metal detectors, according to Hecox. Their sensitivity can be set to detect motorcycles, but the proper balance is difficult to adjust, he said.
California has chosen a technological solution. A law adopted last year requires that when new traffic-activated signals are installed, they be capable of detecting motorcycles and bicycles."
"The traffic lights in question are controlled by devices buried under the road that operate similar to metal detectors, according to Hecox. Their sensitivity can be set to detect motorcycles, but the proper balance is difficult to adjust, he said.
California has chosen a technological solution. A law adopted last year requires that when new traffic-activated signals are installed, they be capable of detecting motorcycles and bicycles."