For 1999, the RM250 combines smooth power delivery with more kick across the powerband. Its crankshaft has less inertia to allow the engine to rev more quickly, which you'll feel as stronger acceleration, and everyone else will see as a monster roost. To increase mid- to high-rpm power, the cylinder features new port shape and timing, while the PowerJet carburetor has an improved spray pattern. In addition, the exhaust valve has been modified to deliver more consistent power throughout the powerband. For better engine performance overall, the crankcase's cylinder base intake area has been revised.