A piece of crap blocking fluid return to your master cylinder can cause this.

I found once that a piece of 'O' ring material off the master cylinder piston acted like a one way valve and wouldn't let fluid return to the reservior. Locked the rotor up tight but when the bleed fitting was opened and shut I could use the rear brake one time then it locked up again...

OR

If your caliper pistons are dragging due to crust, rust, or whatever that's a different story, although not likely on an 09 yet. Don't know how many Ks.
You would need to pull the caliper off, disassemble the pistons from the caliper, clean everything out and get new O rings for assy.

Or try this:
Open the bleed fitting and retract the pads just a little bit. Get two fairly thin copper sheets to use as shims, cut smaller than the pads and leave a small 'handle' on them. Insert one on each side between the pads and rotor then do a normal bleed. When you have all the air out of the system by doing a normal brake line bleed remove the copper shims.


I'm betting on a piece of crap blocking return flow to the master cylinder.
What this will do is to allow the pads to stand off the rotor just a teensy bit during normal operationand should stop any drag.





Good luck and let us know what you find.

Cheers,
V2

YEah I missed the bit about being an 09--and it was in the first sentence... guess I'd better wake up. The stuff I posted was for the reliable EVO models. As far as the new fangled ch1t I know nothing-- better make sure your ABS works after doing the bleed.

Hope you got it right-- let us know how it goes...