Headlight cracks

[Grumpy Goat]

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Somewhere along the line, one of my headlights became cracked (see photos below). Years ago I had been experimenting with brighter bulbs (some xenon) and it may have been the heat associated with those. To what degree do you think the cracks affect the beam? I don’t want to compromise the output, throw, or annoy oncoming vehicles.

You second photo is the best for illustrating the problem, which in my opinion, was caused by excessive heat. The through-thickness cracks seen in the photograph are new refractive surfaces in front of the light source, whatever it is, and will absolutely affect the projected beam. I suspect that it will become more scattered / less focused and will likely increase the glare to oncoming drivers. This is a worse scenario than slight pitting of the outer surface of the lamp over time.

There is no fix other than replacement of the assembly. You may want to look for a good condition second-hand lamp assembly, e.g from a salvage yard or on eBay. New is expensive, as you may have already found out.