Eventually road 15 km against the wind in highest assist. The motor and refurbished battery were both uniformly warm.
There were no hot spots on the battery in the one minute dummy load test so this is not surprising.
Range in medium assist increased from 40 km to 60 km, flat land no wind.
Now the bad news.
Water filter clogged up and I rummaged around for a fresh charcoal filter. Found 2 spent ones -- just about all the charcoal I needed for the dummy load. I wasted $5 on a bag of charcoal!
Something like this was exactly what I was saving them for. I got to much clutter to be making unforced errors like this!