Well you shold leave bearing into some paint thinner for at least one minute and affter dry off real good but its kind of a risk if you do not dry of bearing good and quick it could get rusty noisy and responsive
I would also recommend cleaning the bearing with paint thinner then drying it with some compressed air. If you don’t lube it the bearing might rust but I take that chance because it spins a LOT longer without lube, lube just slows it down. Or you just might need to break it in.
if it is a stock bearing there is no reason to clean it,when it become noisy its broken in,also,dont worry if it gets brown,that means its broken in too.