Are brake rotors supposed to spin easily?
 

A week or so ago I replaced my brake pads. When I spin the rotor, it doesn't spin freely. Looks like the pads are touching the rotor, but not too much that you can't turn them. I forgot to check on how they were with the other old brake pads. Driving, I don't notice a difference from before and now. Also, since currently I am working on lower ball joint, I took the calipers off. The rotor spins freely because of that. So that made me think.

It's normal for the brakes to drag a little bit. You should be able to turn the rotor pretty easily by hand, but probably can't spin it more than a fraction of a revolution. Sounds normal.

My $.02

- JimY

Thats exactly what I got.. its easy to spin by hand, but it won't keep spinning around.

The rotor won't keep spinning when you lift your hand. The mass of the wheel will allow it to spin longer. There should be a drag spec in the manual, and possibly separate specs with and without pads so you can check bearing drag as well. I don't know how it's checked in MBs but for a car I used to have you tie a cable to one lug, wrap it around the other lugs then measure with a spring scale.

Sixto
95 S420
87 300SDL

Rotor drag like you are describing is normal for disc brakes. The pads always touch the rotors, causing the slight drag you feel.