I count to 45 and legally go through the light -- Wisconsin state law says bikes (motorized and pedalled) need to wait 45 seconds. If no car is present during that time to trigger the light, we may proceed through the light.

That said, DH and I both have steel frames. If we know where the sensor is we put one bike on each vertical border of the box and tip the bikes toward the middle. Sometimes that will trigger the light.