[Ducati] 96 900SS/SP Master Cylinder Rebuild Info Please

[Alex]

Large bolt masters are rebuildable (and Brembo sells kits).  Small 
bolt are not intended to be.

Large bolt have a metal piston, small bolt has plastic piston, and 
rebuild kits have a new piston and o-rings.

You can disassemble the small bolt type and clean them up.  U-cup 
type o-rings can be bought in the aftermarket (make sure to get EPDM 
material for brake fluid compatibility).  I've done this with my 
masters and have had zero problems.  The EPDM material will outlast 
the Nitrile type by about 10 years and the U-cup type o-ring has a 
better seal and scraping functionality.