I have been having problems with the caliper on my avid juicy 7 brake system (rear only). The pistons will not fully retract into the caliper body. As a result, both sides of the pads constantly rub on the rotor disc. I have taken it to 2 LBS's for adjustments with no luck. Last week I took it to be bled. The shop called SRAM who thought there may be water in the system and bleeding it should solve the problem. No luck again. I hate to go out and spend the $ to replace it but this is ridiculous. Anyone with any ideas?