my xtr wheels out do my

mavic ssc sl's when i pick up my rd bike with the
mavics and spin the rear wheel, and do same on my
mtb with xtr hubs the xtr wheel spins longer so with
that result i would think the mavic wheel is slower
the ssc mavics have 900 miles on them, my xtrs have 3k
and never serviced, whats up with that? the front wheels
on both bike coast about same amount of time when i did
the hand spin test.

 

Hard to say. The Mavic uses cartridge bearings. Don't know about the XTR... Probably cones.

Typically Shimano hubs are standard cones with kinda crapy seals. Perhaps the XTR has better seals being an ATB hub.

I've heard that the industrial style cartridge bearings tend to have more resistance, at least from the seals, than do the cup-cone bearings.

Also note the cup/cone bearings can be adjusted to run "loose" because "you" must adjust them. The cartridge bearings typically are not adjustable... Actually care must be taken *NOT* to apply too much side pressure or the bearings will bind in the races. This is usually accomplished by the bearings being "pressed' into the hub and a spacer applied to each side of the inner race to help equalize the forices on the races to keep them in alignment.

My tandem's aerospoke wheels also seem to have higher drag esp at lower rpms in the "free rotating" position.

Not sure if there are any answers here except that the world is going to cartridge bearings because they are easier to service (because they are not serviceable)... Um I mean they are easy to service because you don't have to find threaded cones or worry about external seals and such... I had to replace a bad bearing in a brand new set of wheels recently and unlike cones, I could simply order the bearing by part number from an industrial bearing warehouse for $9. Nice that the parts are standard and not so bike specific now.

The price we pay for compatability with other industries?

 

Cartridge bearings have more resistance in general due to the mechanics of the design - there is more friction. This is probably the main reason that Campy and Shimano stick with cup and cone designs for their hubs, even the high end ones.

 

does the ratchet noise slow the wheel down any, it kinda loud
and when i pick up bike and spin rear wheel i can feel the
ratchet clicks thru the frame

 

the ratchet can effect the friction on the rear wheel but one must also take into account that a wheel with a higher rotating mass (ie. mass towards the outer edge of the wheel>rim, tyre etc.) will inherently spin for longer but will also take longer/more force to start the spin. The actual difference between the two wheels "on the road" will be negligible. You are more likely to notice the difference between the weights of the wheels on the road than the friction within the hubs.