Can we talk about how much grease is actually in a sealed cartridge bearing?

I was rebuilding an old Shimano hub last night and decided to pop one of the sealed cartridge bearings open just to see... I was shocked to find it was maybe only 30% full of grease. I always assumed they were packed solid. Found a tech document from Enduro Bearings online that basically said under-filling is normal to prevent overheating. Blew my mind a little. Anyone else run into this and have a preferred re-packing method, or do you just leave them as-is?

2 comments

2 Comments

troythompson3d ago

That explains the dry sound some new hubs make.

felixramirez3d ago

I packed my new DT Swiss hubs with a heavier marine grease and it quieted them right down.