2 strokes dont engine brake as they dont have camshafts,valves,large oil pumps and such run off the crankshaft,this stuff still turns on a 4 stroke when you shut the throttle causing the crank to slow, i think 4 strokes run higher compression as well.But there is a form of engine braking on a 2 stroke its called gearbox braking, if you ride it right you bang it down the box with the revs still high to keep it in the power band. To Quote Stepthen RC45 "Keep the bugger revving"