My TR-4 is negative ground.

I don't recall the type of electrics it had, but I do vividly recall traveling around 75 or so mph on a dark night aboard a new 1965 (I think) BSA Lightning when the lights suddenly went out. I found the experience quite exciting for a few moments. In fact I believe I was wearing my goggles like contact lenses.

As a youngster I also had a little BSA Bantam with a headlight powered by the magneto. At night it could be dangerous to slow down as the light diminished in proportion to the RPM.

I expect that had I known then what I know now, nothing would have been as much fun.

jess