New rotors on rear should I adjust parking brakes in?
 

One rotor on the rear of my 190d was no longer flat so I am replacing both rears; they came off so easily I was amazed. With the new ones on, there is a certain amount of drag on the parking brake shoes. This is before the calipers are installed btw. I guess Im wondering if these should be as tight as conventional drums would be or if I should draw in the shoes a little bit? I'd hate to bake my new rotors the first time out!

The adjustment procedure calls for you to adjust them until you feel them drag and then back off until the wheel turns freely...usually just one or two "ticks" on the adjuster-wheel. You should not leave them so they drag, in my opinion.

Follow the procedure above. Don't allow them to drag. You will glaze both the shoes and the inside of the rotor/drum. Those things get super hot if they are allowed to drag at all.

If your old rotors are not scored in the e-brake shoe area, and your e-braked worked fine before, adjustment may not be needed.

There could have been some wear on the inside of the old rotors from the years of use of the parking brake, and also they might not have made them exactly the same ID as the replacements...the thing is, if they drag they should be adjusted.

I pretty much thought so too. The plain fact is that I've never used my parking brake. Theres no point in binding up a rusty cable. But feedback is valuable. Thanks guys. My thought was that the new drum would be smaller in diameter than the old, making adjustment of the shoes necessary. BTW, I do have one good rear rotor available for shipping costs--