Help with BD36 diagnostics

Quoted from Endless-Sphere:

I can think of two things:

1. You're having the same problem I did with my batteries. When you accelerate, you draw a lot of amps from them and hit the LVC on the controller. A fraction of a second later, they bounce back (because they aren't actually dead) and allow it to run again. This continues until you're going faster and not drawing as many amps, so the batteries don't sag enough to hit the LVC. This makes sense because the batteries would stay below the LVC longer as they age and deteriorate.

2. There's a problem with the brush assembly. There could be something on the commutator plate that interrupts contact with the brushes. Clean it off and it should go away. It's unlikely that this is the case, but possible. I'd suspect the batteries first.

If it's not the batteries and you need help taking apart the motor, I could post a picture tutorial. I run 72V on mine, so I need to see what the brush wear is like, anyway. 8)