R1100GS Master Cylinder

[RoboBoxer <roboboxr@xxxxxxxxxxxxx>]

I have been having reoccurring problems with the front brake lever hanging
up. Upon disassembly of the front brake lever, and removing the rubber boot
on the master cylinder, some type of corrosion is found. I've removed the
master cylinder piston twice and cleaned up the bore. I've cleaned the
piston and seals, and re-installed using the original components. The
corrosion came back once. I'm not sure if I just need a new rubber boot to
seal better or should go ahead and replace the piston and seals as well as
the rubber boot? 

Anyone experience this type of problem before?
 
Regards,
Paul T. Donoghue

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