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pale rider · 08-11-2008, 08:04 PM

if opening the bleeders does not release the pistons then it cannot be a problem with the master cylinders. The problem is in the calipers. The seals are what acts as a spring to retract the piston on the calipers: they are asymmetrical and they cant slightly in the cylinder to put retracting pressure on the piston , so having set for a long time the seals may be gummed up and not retracting the pistons. Try replacing the seals and cleaning the pistons and bores, then lube them with brake fluid before reinstallation. and be shure to get the new seals in the correct orientation.

08-11-2008, 08:04 PM	#4 (permalink)
pale rider Junior Member Join Date: Jul 2008 Last Online: 09-19-2008 10:18 AM Location: colorado springs My Ride: 83 XR500R W/tags, 91 VFR750F Posts: 10 Thanks: 0 Thanked 0 Times in 0 Posts	if opening the bleeders does not release the pistons then it cannot be a problem with the master cylinders. The problem is in the calipers. The seals are what acts as a spring to retract the piston on the calipers: they are asymmetrical and they cant slightly in the cylinder to put retracting pressure on the piston , so having set for a long time the seals may be gummed up and not retracting the pistons. Try replacing the seals and cleaning the pistons and bores, then lube them with brake fluid before reinstallation. and be shure to get the new seals in the correct orientation.