Years ago I added a Whelen TIR3 to my GS, loved the thing. Recently decided to add one to the Norge, bracket is done and most of the wiring. What I think I'm learning from my voltmeter is the the brake light circuit is being fed a constant 7 volts, and gets fed 13 volts when the brakes are on. Poking around here, that appears to be the case with other bikes with LED tail/brake lights. I don't want the TIR3 to be on all of the time, only when I'm braking, so... I'm wondering if I can use a 12 volt relay to isolate the LED brake lights from the TIR3's. If I'm reading the specs correctly for a Bosch relay, the pull-in voltage is 8 volts, and the drop out voltage is 1.2-5 volts, which in this case wouldn't do anything for me. My electronics engineering experience is so far in the past that I've forgotten much of it. Can any of you electrical/electronics whizzes think of a way to isolate the TIR3 so that the TIR3 is only on when the brakes are applied?