As some of you may know, when I installed the 7" Lucas headlight on my G5, it pointed the beam down at the road about 15 feet in front of my front wheel.
To get the light to point down the road like it should, I slotted the two lower screw holes in the chrome headlight rim so I could move the bottom of the light forward to aim the light beam up.
All fine and dandy except the lower area of the rim would move forward almost to the point that it would disengage with the screw head if I revved the engine up to a speed that caused high frequency vibrations.
Even adding a nice flat washer and tightening the screw as much as I dared didn't fix it.
Today, I went to my handy hardware store and bought some external tooth, stainless steel, "star" type lock washers. The kind that have a bunch of teeth going around the outside edge. They cost about 17¢ each.
After installing them on the two lower screws I rode several miles revving up into 5000 rpm zone many times.
So far it seems the teeth have bitten into the chrome rim as it hasn't moved at all.