2004 Yamaha YFM660 Grizzly 4x4 Make: Yamaha Model: YFM660 Grizzly 4x4 Year: 2004 Compatible Tire Sizes: 25x8-12 25x10-12 26x9-12 26x11-12 Stock Tires Size is 25x8-12 Fronts with 25x10-12 Rears