Unrivaled 2-stroke Performance 2 stroke single, adjustable power valve, hydraulic clutch, 5 gearWith enough power to excel on all sorts of tracks and terrain, combined with an extremely lightweight chassis, the 250 SX has 1 of the best power-to-weight ratios in motocross. The unrivaled performance of the lightweight 2-stroke engine makes it a true contender against the more complex 4-strokes. For model year 2016 the 250 SX features detail improvements and new colors and graphics, but basically retains the same chassis and engine specification as model year 2015.