Friction: Sealed Hub vs Loose Bearing Hub
I've just entered the 21st Century and got a bike with Mavic Ksyerium wheels. They seem to have more friction than my old Campy Nuovo Records from 1980. Is there anything I can do ?? I used to rebuild my old hubs and get them perfectly adjusted for minimun rolling resistance, but when I give these wheels a light spin, they seem to stop too soon. It's late, and I was just messing with the hub trying to fix a problem with the cassette (see other post), and wondered about this too.
Doesn't seem that these are meant to be serviced much ... not easy to get the hub body off and on elegantly. Maybe I'm missing something.
I have wheels with both sealed and loose bearings. I find that the sealed bearing units roll smoother after they have been used for about 50 miles. So far I have about 1000 miles on a set of sealed bearing wheels with no problems. Took them apart to check on things at about 500 miles and all looked fine. Next check will be around 2K (unless I hear noises)!
I do agree that a properly adjusted set of loose bearings will show better rolling when spinning it in your hand. Not sure of the comparison when loaded with a rider.
Most of the drag is from the seals and these will wear in and loosen up a bit when you have some miles on the wheels but they will probably never quite equal a properly adjusted cup-and-cone bearing hub when spun under no load.
I have read, but seen no data, that sealed and cup-and-cone bearings have nearly identical drag under load despite the difference under no-load conditions.
Finally, at worst the real differences are so small as to be negligable. Maybe a fraction of a watt at 30 mph.
I suspect the amount of drag you are talking about is going to be absolutely, completely, totally negligible when you are actually riding. Having a really close shave before you ride will probably have more impact on the friction you're fighting.