Crazy voltage sag below 60v?

My vesc sat in parts for a few months. When I first built it, it felt horribly saggy and had very little torque. I assumed it was my tune or there was discussion it could be my IMU was faulty. At that time I was pretty sketched about running no BMS too, so I’m not sure I ever let it fully charged and was trying to keep the voltage between 20-80%ish. That was on a CBXR battery pack.

I got it back together with a stock XR pack a couple weeks ago. After doing some reading I felt better about fully charging it and did so where it was from anything flammable. At full charge it feels way better! Way more torque. So I went on a small 2-3 mile ride with the kids to some testing and learning.

We didn’t go far and decreased elevation by about 200ft. Not far in the board started feeling super saggy and eventually became horrible to ride. It seemed to shut off (not power off, but had to stop and restart from 45) after a couple little bonks or spays/reverse wheelspins. I ended up calling my wife to bring me back because I didn’t think it would make it back up the hill. My voltage was at 59v at that time.

I was using stock 5.3 and the settings I copied from customewheel.shop. I will post a tunecard later, but I am confused why I got this behavior but @hannes and others have not. I will try other fw and tunes/settings soon but curious why my rig is behaving this way. Any help is appreciated.
Thanks!

You might be a victim of a VESC default configuration. After running the motor wizard YOU MUST update the Voltage cutoffs in Motor General - Voltage to 2.5 * cellcount and 2.7 * cellcount respectively or else the controller will limit the voltage very early on

I consider 49V pretty much empty, barely enough to coast back to the car/house on flat roads