2002 Yamaha YFM660 Grizzly factory service and repair manual, Page 320Get this manual
FRONT AND REAR BRAKES
DISASSEMBLING THE BRAKE CALIPER 1.Remove: Brake caliper piston Dust seal Caliper piston seal Removal steps: Blow compressed air into the hose joint opening to force out the caliper piston from the brake caliper body
WARNING
Never try to pry out the caliper pistonCover the caliper piston with ragBe careful not to get injured when the piston is expelled from the master cylinderthe caliper piston seals