Originally Posted by
jputnam
Road crew I used to have to deal with on these used an un-laced Mavic MA-2 as a test target. Properly adjusted, an inductive loop can detect a single aluminum rim placed properly over the most sensitive part of the loop.
Better to use an aluminum mtb wheel with fat tire on. The closer the rim is to the sensor the better it works, a bare rim will be too close.
Locally (quadrupole type) the best result I get is with my CF roadbike, aluminim rims with 23c tires. My steel mtb with Al rims and fat tires misses a few my road bike always triggers.