Well, it's been a very long time. I have actually been using the board as much as I can - it's been working very well with my idea to use the charge adapters and a parallel board. Charging is a simple matter of unscrewing the watertight box on the side of the battery carrier, connecting the main, balance and temperature sensor connectors to the charger and then setting it to balance a 6S. I've been getting a pretty consistent figure of 6Ah put back in the batteries after a day's trip to work and back, so I've spec'd the li-pos pretty well, and they charge properly. Every few charges, I take the carrier off and balance each battery individually. That's been working very well.
Sadly, disaster has struck again, and this time it may be fatal. I think the motor has burned out. Last week, I noticed performance was down a little when first setting off, and the motor was making some odd noises. They cleared once the motor warmed up so I didn't think much of it. Then on Thursday, on my ride home, I hit a bump and the whole thing rolled to a halt. At this point I could smell burned electrics, and when I lifted the board up, there was smoke coming from the motor. I flipped the power off but I guess the damage is done.
The screws holding the motor housing together were badly warped from years of abuse (probably before I even got it) so it's taken me a while to get the tools to get into it. However, when I pulled the end caps off, I discovered the housing is
the motor - the end caps hold the armature bearings and the permanent magnets are attached to the tube. The bearings are still good, but there's a strong smell of burning from the rotor even now.
It's a plain brushed DC motor. There are scorch marks around a couple of brushes in the end cap, and the armature is covered in metal filings, which seem to have come off the magnets. At a guess, the magnets have worn away and worked into the electrical path, where they shorted out something. The wiring doesn't look burned, but whatever caused the failure sucked a lot of power through - the casing was untouchably hot and trust me when I say it stinks!
What are the chances of repairing the motor? I've got a sizeable investment in the board now, I'd rather not bin it. The chance for replacement is next to zero since the company is long defunct.
What's more annoying is that we actually have a summer in the UK this year, I'm missing out on using it!!