D.I.D MXY-004OEM 520DZ2 Gold Chain and 13 Teeth/49 Teeth Sprocket Kit Fits: Yamaha YZ450 F (2007-200199)/YZ450 F (2014) D.I.D Chain Model: 520DZ2 Non-O-Ring; Chain Color: Gold; Chain Length: 114; Gearing (Front/Rear): 13T/49T (Stock Gearing) The redesigned 520DZ2 chain has a projected wear life of twice that of the 520DZ, with a total of 4 times longer than standard chain under similar conditions Features exclusive SDH pin treatment that forms an extremely hard chromium carbide layer on the pins surface while maintaining a soft inner core resulting in extreme impact strength while maintaining outstanding shock absorption High carbon steel rear sprockets are heat treated for maximum durability and long life, Countershaft sprockets are made from chrome moly steel for superior strength and durability