When restoring my Aero 125 (a.k.a. NH125 or Lead 125), I found that the low beam was burned out in my headlight (Part #33120-KG8-670). I soon discovered that these headlights haven’t been made for years, and there are no new ones available. Used ones are selling on eBay for near $100, but these are coming out of trashed scooters and are destined to burn out soon. So, I decided to retrofit the headlight assembly to use modern, replaceable halogen bulbs.
While these instructions were made for my Aero 125, they also will likely work for similar, older scooters with sealed beam headlights (e.g. Aero 80, Elite 125, etc.). Your mileage may vary.