The main repair today was the broken wire from the controller that leads to the batteries. I stripped back about an inch, and on the positive, I soldered 20 cm of 10 awg wire. This is the very flexible wire from Hobbyking, ideal for situations where the wire is going to be stressed and flexed. I would have also soldered the negative, but that wasn't feasible, so I used a 60 amp terminal connector instead. I tested it, and that worked.
Next, the front brake; the cable conduit has been jumping out of the holder, leaving me without a front brake. I think I've fixed it, it just needed the gap to be made less wide. Usage will tell me if that's done the trick.
Third, the batteries. I have the 4s batteries taped in pairs, which is ideal for a 24 volt system. But since the Xiong Da is 36 volts, I've changed that so they're taped in threes.
I've also added a couple of short lengths of wire to my repair kit, and a couple of terminal connectors.
Ready to roll again!