I bought a high spped servo from hobby partz for my ecx torment to try make it turn better. When I put it in the truck and turned it on it makes a sizzleing noise( which I hear is normal) So with a fresh charged battery I tried driving the truck. It went about a foot and died and then started acting up( wheels turning back and forth and actually getting stuck in forward). I charged the battery on my new thunder ac680 charger. ( not sure why it says it charged it to 9.2 volts when it is a 7.2 volt battery). So I know there is enough of a charge. All the electronics,radio, motor, etc are stock, also the battery is a 1800mh nimh battery. does anybody know what this problem is and how to fix it. Also why doss the charger charge it so high, isn't it supposed to sense the battery voltage and adjust it. Thanks