I just had the DC-DC connector go out after hitting a speedbump too hard. In the process of trying to figure out why the lights went out, I had a look at the connections between the controller and the motor:
Oops. The other connectors in the battery - controller segment have all been upgraded to Anderson PowerPole, but I thought those green ones were heavy enough. Oh well. In a few days, I would have had a bigger failure as the connectors finally made contact with each other.
No corrosion, and no short (yet). This is a stock controller @ stock 48V pack. Only "hop up" is 10GA wire on the supply side from the battery to the controller. When I was upgrading the pack wiring, the phase wires seemed like they would take the current, but those bullet connectors are not reliable. Hence the thread title. They either need upgrading to Anderson or grubb screw terminals or regular inspection.
Did you notice any speed increase with the 10ga wires from battery pack? I have a 45amp controller but still use the tiny wires from the motor. I think it is restricting the current of the controller. Which is ok I guess since the wires haven't fried. Knock on wood. The Top speed is 29mph with 72v so I am happy.
No speed change, just a more secure feeling about the wiring of the pack. The real change was to a series/parallel plug, so the pack could be charged using a commercial 12V Vector charger.
I also have a Suzuki GS motorcycle. It too has generic problems with the same type of bullet connectors in the charging circuits. Any corrosion magnifies resistance heating, magnifying contact resistance and further heating.