Bearing greasing 80% confused!

[sinkerswim]

  Guys, Bryan Young has written that bearings are to be greased to 80%. If you use a bearing packer isn't the bearing always packed to 100%. If packed by hand then I'd imagine 80% would be a guesstimate, from eyeballing it.

Bryan, is 80% recommended so the bearing isn't speed challenged? Anybody?

Thanks

[alantani]

the term 80% comes from the industry standard of an "80% fill" described by the okuma product developers when we were talking to them about the bearings that they import from japan.  apparently the bearing industry uses this term to describe a bearing that is totally packed with grease.  the balls and cage take up 20% and the grease takes up th rest. 

[sinkerswim]

Thank You Alan! Now I get it!