This is not true, at least not in any place I've lived in the US. On a (motor)bike you do have to be careful with your wheel placement: align one wheel with black lines on the ground, which are sometimes circles and sometimes straight line segments, and stay there. Even with really skinny bicycle rims the sensor will note your presence. The only difference to cars is that automobile rims are much wider and twice as numerous, so it's harder to miss the sensor.