Have you replaced the igniters? Have you re aimed them?

 

Can you explain more please?

 

Just to clarify please, is this due to the yellowing and frosting of the outside lens of the headlight, or is it actually the light itself that is dim. I have never had a headlight bulb itself go dim they just burn out. But my lens does get frosty and yellowish. For that, I just use the finest polish compound I can find. I personally use some stuff called "Blueout", it's a polishing compound designed to polish out the bluing on chrome motorcycle exhaust pipes. It posts that it is so fine that it leaves no visible scratches on the pipes. For me, it works just as well on the plastic outer frosted headlight lens. The frosting has happened ever since they stopped using glass sealed beams and went back to replaceable bulbs with plastic clear lenses.

 

I had the coverings cleaned but it didn't make any difference.

 

I am going to make a new post which presents the same/similar issue.