THE INVOLVED MOTORCYCLES WERE MANUFACTURED WITH FRONT BRAKE MASTER CYLINDERS IN WHICH THE PLUNGER PISTON BORE DIAMETER WAS HONED .015 INCHES OVER MAXIMUM SPECIFICATIONS. THIS OVERSIZED BORE RESULTS IN A POOR FIT BETWEEN THE ELASTOMERIC PISTON CUP AND THE CYLINDER BORE, WHICH ALLOWS FLUID LEAKAGE FROM THE HYDRAULIC SYSTEM.