Hey guys, so im running R31 rear brakes with a hydro h/brake and a wilwood proportioning valve. Im having the rear brakes dragging and cant work it out ... ive removed the valve out of the master and checked all that ... so ideas?

what have you setup for cable handbrake? nothing to do with that?

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No cable brake but its a spring return so its not that

Dragging rear brakes has two possible causes:
* Hydraulic problems
* Mechanical problems

The usual hydro problem is the Residual Valve thing in the disc/drum master cylinder.
Less often:
* brake lines next to the exhaust system
* collapsed flex hose
* sticking Master Cylinder piston (not returning fully)
* Master Cylinder over-full
* Proportioning valve sticking
* Master Cylinder free-play incorrectly adjusted
* Brake Booster push-rod incorrectly adjusted

Mechanical problems include:
* parking brake adjusted incorrectly, even with no cable hooked up this can cause dragging
* Caliper piston sticking
* Caliper sliding surfaces binding
* Bent or misaligned caliper or caliper bracket
* Dry wheel bearings

R31 rear disc parking brake adjuster

Its both sides and if left sitting they back off slowly so im assuming its hydraulic

Something to do with the hydraulic handbrake master cylinder? A pressure residual valve in that?