Rear brake caliper locking up 2007 R1200RT

I have a 2007 RT with 75k miles and the rear caliper is not releasing. The foot lever has no free play, it has not been changed since it started, so it's not an adjustment issue. I'm pretty sure it is the caliper, my questions for the group.

What's the easier way to narrow the trouble down?
I think just opening the bleed screw on the caliper would do it, if it is the caliper the pedal will drop but the caliper will stay tight, if it is the pedel adj or MC, the caliper will release and everything else stay somewhat the same.

Anything else I can look at beforehand?Anything I need to be careful of in replacing parts and bleeding the system?
The bike still rolls so it's not a complete lockup yet but it sure gets hot. I can still rattle the abs so I don't think it is causing any problems.
Thanks in advance.
Ron

I would open the bleeder on the caliper (with a hose to a drain bottle attached!) to release any hydraulic pressure.

If the wheel is then free, before looking at the caliper I would look at the brake rear hose -- they can internally fail and act as a "one-way valve," allowing pressure to be pushed from the ABS unit to the caliper, but not allow that pressure to bleed back off upstream to the ABS unit when the brake pedal is released.

Ron,

Please read: http://forums.bmwmoa.org/showthread.php?t=46055 - I've added the info to your thread title. It's helpful if you want people knowledgeable about your year/model to open the thread. It's also helpful if other people search for the topic later on.

Thanks for your cooperation.

The reference to no pedal free play makes me wonder.......

I'd suggest you begin by just pulling the caliper, removing the pads, and blowing some compressed air into all the nooks and crannies and trying to work the pistons and the sliders in and out a little by hand. It could just be some dirt has gotten into it or maybe a little brake lube is needed at the sliders.