Re: Has anyone tried those things that are supposed to trip traffic sensors @ red lig
I've been using a Signal Sorcerer for more than 5 years now on 3 different bikes ('01 Triumph Thunderbird, '82 Kawasaki Spectre and '08 Triumph Scrambler, my current ride) and they do work. As you said, they are basically just a powerful magnet that you affix to the lowest point of the bike and try to position right over the wires of the induction loop. I would say they work on 95% of the lights around here.
In most cases I rode the bike for several weeks before getting the SS so I was able to ride to the intersections without the SS and then with it, and the difference was dramatic.
The older SS was a rectangular strip that seemed to fit well on the frame of the bike. The newer one I got for my Scrambler is a round disc. IMO it's not as easy to stick onto the frame. It also doesn't work as well, although that could also be because the bottom of the Scrambler frame is farther from the road.