Surprise update, May 19th: Gotway now uses stronger wiring for the motor cables going from the motor to the connectors. They have been convinced by a dealer. Not sure how much it has to do with this So the problem is extremely unlikely to appear again and can be considered solved. June 23rd: it is a general problem that the wheels can produce higher currents than the cables can take, so melting is inevitable under the right circumstances. See this thread for a more up-to-date discussion (the exa