So, I've either got or fix up a fair amount of old bikes. This means a lot of cup-and-cone bearings. One thing that hasn't always been clear to me is whether one needs "pre-load" - meaning a little tight (right?) or leaves things a bit loose (for hubs) and allows the QR to tighten it up a bit for hubs...and just barely zero play for BBs. I did things this way and ended up thinking I left things a bit too loose as both hubs and the BB ended up developing some play pretty quickly. Alright, I figured, I need things a little tighter than that. So, I make things a little tighter. So far, so good. However, I recently noticed grease oozing (oozing isn't a big deal, I really load grease in there) from my rear hub. The grease I use is Teflon based and white. The oozing was pretty gray looking and I originally just put it in there a couple of weeks ago, so, now I'm worried things are too tight and some metal is getting ground into the grease. So, any thoughts? How tight should these cup-and-cone bearings be?