Hola Frankenbiker,

Yes, its amazing to me that they sell these Optronics lights to mount on automobiles, and the trim rings do just bounce off in normal use, despite being difficult at times to get on and off when you have them in your hand (and dimples are not symmetriclaly spaced either, so you have to line them up!). I'd read about the trim rings falling off somewhere along the way in this thread but went back and forth between tape and caulk, ending on tape as you suggest, for fear of not being able to remove the trim ring for bulb replacement when the time comes if I use caulk.

I do have a fuse, but you could only see the remnant of the fuse holder in the photo, it's the red plastic box poking through and you'd have to know it for what it is in order to be able to identify it in that first photo I posted. Couple more detailed photos below, and then a non-bike system I built with a real fuse to provide some longer duration battery back-up for my AC powered water pumps in my basement! (but that's a different thread in some other forum)