Originally Posted by
canklecat
he main difference I've noticed between my various cup and cone loose bearing hubs is the condition of the cones. Some of the used bikes I've bought had pitted cones. I could feel the grinding just twiddling the axle with the wheel off the bike. Usually I can improve the feel and reduce the rolling resistance by carefully adjusting the cones to minimize slack without increasing slop.
I suspect many mass produced loose bearing hubs are assembled quickly, cranking down the cones and setting the lock nuts without much finesse. The cups and bearings are hardened but the cones are brittle on the outer layer and chip easily. Just a theory.
I've noticed that loose bearing Shimano hubs are consistently tighter than they should be. If it were just an assembly issue, the tightness of the bearings should vary but it seems to be about the same no matter what hub is used. My working hypothesis is that this is done intentionally to aid in machine assembly of the wheels. If the hub spins a little less freely in the machine, the robot can line up the spoke more consistently. The hubs should be adjusted before sale but this isn't done on a regular basis.