i was running 3s 5000mah from stock no prop change and was fast but burned out the bearings in the motor. so self righting is set for 3s no problem. also i was checking my other boat also exceed sword and the stock motor is 2848-2636kv and i bought a new motor also thinking it was the same Eurgle 2848 2580kv and the boat isnt as fast either any help on that one if you can, prop change? up or down? about to look at the page you suggested also