Originally Posted by rjberner
So I guess the moral of my story is if you have disc brakes, leave the wheels / brake system intact for the most part. And needing consistent, 1mm or less tolerances on a six-foot bicycle frame makes about as much sense as biking in the nude.
FWIW, we have been using hydraulic and mechanical disc brakes for about 8 years.... Once you get the brake pads bedded-in and properly adjusted, the calipers are not adversely affected by wheel removal.
This is not to say your observation about the Avid is unique... I read a similar post from someone who opined that they would be reluctant to have one on their front wheel given how often it is removed and the problems associated with getting it dialed back in. Several other readers immediately chimed in to suggest this is not the case.
Therefore, having worked on a bunch of tandems with an Avid disc on the rear wheel -- including our own -- if yours is giving you problems take it back to your dealer and have them make it right; it shouldn't be giving you trouble. If you want to fiddle with it yourself and if you're having a hard time getting the tolerances between the pads and the rotor then there are two suggestions:
1. Install a booster (compression) spring between the cable stop and pinch bolt on the caliper (which is what I did with our Avid and all of our riding companions), or
2. Consider adding an in-line Travel Agent or BPB (Brake Power Booster) -- similar to the device used on road tandems with V-brakes -- to alter the ratio of brake caliper arm movement from the brake lever.
Bottom Line: Unless the caliper or rotor is getting banged-around, once you reinstall a wheel and give the brake lever a good pull, everything should fall right back into alignment, just as you left it before removing the wheel. Doesn't matter if you're pulling the wheel off to change a flat, to clean the bike, or to pack it up for a trip in the car or a suitcase.