Lubricant helps reduce friction between moving parts, but a bearing does not need to be flooded. Too much lubricant can attract grit and make a wheel feel heavy.
A small drop is enough
Apply a small amount to the bearing after it is clean and dry. Spin the bearing gently to spread the lubricant through the race.
Choose the right product
Use a lubricant intended for small skate or precision bearings. Avoid household oils that can become sticky or leave residue.