Originally Posted by Sharkey_t

4 amp charge rate? maybe on sub c cells, but not on a little 2/3a pack, thats just gonna cause them to vent. 2/3a cells typically like to be charged at 1 amp, you can push it up a little bit but they arent forgiving like a sub c nimh cell.

a nimh battery discharge curve is nothing like a lipo. when it has a load the voltage is going to drop quite a bit, even on a fresh charged battery. what you saw on the discharge cycle of 5.39v with a load and they went back to 7.2v when resting is normal.

basicly as i see it, you need to get that low voltage detection shut right off. if it still shuts the esc down what may be happening is the motor is pulling far more current than the pack can supply and the voltage is getting pulled far enough down to shut the esc or receiver down. in that case you have a couple options, either try going to a larger capacity nimh pack (like a 1600-1700mah) or bit the bullet and get some lipos.