Originally Posted by
cyccommute
That has been legal in all 50 states for a very long time. It's part of the Uniform Vehicle Code that all states use as their template for traffic rules. Colorado's Vehicle Code states
A car doesn't have to sit at a light forever until it turns green if the light is malfunctioning. Bicyclists don't have to sit at lights either...if the light is malfunctioning.
I find, however, that a major problem with cyclists and motorists as well as the general public is that they don't have a clue as to how an inductive loop...the "magnet" sensor...works or how to position themselves so that they can actually trip the light. If you ride directly over the wire in the pavement, the light can be easily tripped even by a carbon fiber bike. It's not the bike that trips the system but the wheels of the bike that trip the system.
And then there are companies making products to capitalize on the frustration of waiting at an endless light:
Seattle Cycle Center, Inc. - Amanet Red Light Changer
Although you are quite right, it's not a magnet sensor, it's an induction sensor and so you don't need to have iron and even carbon fiber will cause an induction disturbance if positioned right over the sensor.