The keep sunlight from refracting off the prism of the insect eye, so you can see when the the light is illuminated in bright daylight.Interesting that the parts list specifies 3 of the rubber shrouds, yet I have only ever seen examples of the just the
outer 2 having them. My bike just has the outer 2. My rubber ones have never lost their shape in 15 years.
I've looked at 'em for forty some years but never asked myself "what are they for?"
What do they shroud?
Yes but with issues on 2, the charging unit needs a higher resistance or it stays permanently on with the ignition and as the indicator warning current flow is bi directional, without say a bridge rectifier the led only works for left turns or right. turns.Is there an LED replacement with enough power to obviate this?
My 850MKIIA which came with the plastic air filter box and black cap mufflers did not come with the shroud on top of any of the indicator lights. Probably because its a UK/European version which was shipped to me direct from Liverpool.
Seeing how the 2 outer lights could possibly be seen from the sides of the motorcycle I believe the last sentence of the law makes the shrouds necessary. I could be wrong though, there might be another reason. My older BSA's never had any shrouds over the indicator lights.