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Stuck at a Light

I've seen ads for those add-on units that are supposed to trip traffic signals so we don't have to sit through five cycles. Have you ever tested any?
Phil Harkins
Brandon, MS

_Actually, we have tried them and they made a difference. The most common sensor that motorcyclists deal with is the inductive-loop traffic-detector system. According to Steven G. Goodridge, Ph.D. Member, IEEE, “These operate by sensing disturbances to the electromagnetic field over a coil of wire built into the roadway. When a conductive object enters the area over the wire loop, the magnetic field generated by alternating electrical current in the signal-detector circuit induces weak electrical currents in the conductive object. This change is detected by the circuit instrumentation in the signal controller cabinet, which then tells the signal.”

_The “loop” of the sensor is typically seen as a geometric shape cut into the road surface and covered with tar. It senses conductive material, so it doesn’t need to be magnetic or iron or steel. Parking with your wheels on top of the sensor lines gives you the best chance of being detected. If you see a sensor pattern that looks like a rectangle or square with a line down the middle, park over the center line—it’s the most sensitive. If you are riding in a group, try to cluster as many bikes as possible over the sensor lines. Tall bikes with lots of ground clearance seem to have the most problems. Some riders claim that putting the kickstand down on the lines helps. One rider ran 14-gauge wire around the sole of his boot and steps on the sensor lines. _

_Laws differ, but some jurisdictions allow motorists to proceed through an unchanging light, with restrictions on conditions. We’d research that before risking points on our driver’s license! Once you have identified a problematic left-turn lane, consider turning right and making a legal U-turn. Another common solution is to leave the bike parked while running over to the sidewalk and pushing the pedestrian crosswalk button. That’s a sure ticket no matter where you live! _

_The sensitivity of an inductive-loop sensor can be adjusted, and many riders report that notifying the highway department resulted in quick action. If your local jurisdiction proves slow to react to a motorcyclist’s complaint, try telling them the sensor isn’t recognizing your bicycle. Many cities take pride in being bicycle-friendly. Motorcycles? Not so much... _ _