2007-2009 Kawasaki KFX50 service manual, Page 201Get this manual
13REAR WHEELSWING ARMHYDRAULIC BRAKE Remove the pistons from the brake caliperUse compressed air to press out the pistons through the brake fluid inlet opening and place shop towel under the caliper to avoid contamination caused by the removed pistons
Push the piston oil seals inward to remove themClean each oil seal groove with brake fluidBe careful not to damage the piston surface