motocross

Engine: The fuel-injected 449cc engine uses the cylinder head and cylinder from the YZ450 for superb power characteristics. Power deliver is smooth and strong off the line with lots of low and mid range where you need it. As rpm climbs you?l find the same top end punch that has made the YFZ450 such a fierce competitor and class leader.The new crankcase holds the newly designed crankshaft that? ready to handle the increased torque output, as well as the counterbalancer that has an increased ratio for superior vibration control. The crankcase also houses the oil tank, which helps to centralize mass for unmatched handling and makes maintenance easier.Camshafts are all new for this model, and are designed to maximize the torque available in the low and mid ranges.Fuel injection uses a 12-hole injector that provides exceptional atomization of the fuel for maximum combustion efficiency and power delivery. The system also uses a big, 42mm Mikuni?throttle body and includes ISC (Idle Speed Control) for easy, reliable start-up and warming.Engine Type 449cc, 4-Stroke Single, Liquid Cooled w/ Fan, Titanium 5-Valve DOHC Bore x Stroke 95mm x 63.4mm Compression Ratio 11.6:1 Fuel Delivery Yamaha Fuel Injection (YFI), 42mm Ignition TCI (Digital) Starting System Electric Transmission 5-Speed Manual Clutch Drive Train 2WD; Sealed O-Ring Chain, Eccentric Adjustment

Bore x Stroke 95mm x 63.4mm