YAMAHA YZ250X This was the Big News. Yamaha pulled the sheet off a new two-stroke off-roader based on the YZ250 motocrosser. The YZ250X is designed as a pure, closed-course competition lightweight two-stroke GNCC/woods racer. Features specific to this new model include an 18-inch rear wheel, a sealed O-ring chain, a wide ratio transmission, a narrow expansion chamber, off-road-focused tires and suspension settings, plus a standard side stand and a fuel tank petcock with reserve position. The 2016 Yamaha YZ250X will be available in August, priced at $7,390.