With the new motor in place, 48 V battery pack and the electronics in shape all major things were done. A few things were left for later.
On the golf cart motor, the brushes were protected by an aluminum mesh cover. Unfortunately it was coming apart due to corrosion. Something had to be done to protect the brushes before I got time to weld a new motor cover. I simple 3D printed wrap actually turned out pretty OK. Ugly color but it ensures not too much dirt and rain gets into the motor.
The previous solution for the speedometer using a reflective optical sensor didn’t work too well. It was sensitive to noise and needed a delicate trim to not glitch. Instead I replaced it with a Hall effect sensor and glued a magnet to the outgoing belt pulley. No more glitches!
After the initial testing of the motor I found the accelerator to be very jerky. It was almost impossible to go slow or hold a specific speed. Using the Curtis software I noticed that the registered throttle position jumped around widely.
This was a clear indication that my previous potentiometer swap in the pedal box hadn’t been successful. Or at least, the later modification of it had failed. I had to modify the potentiometer from a 22 kΩ to a 5 kΩ keeping the 45 degree range which didn’t go too well. So I had to find the correct spare. That had previously proved hard but with some new energy I searched the web and found out what to look for. Original Curtis spare potentiometers were expensive (€100+) but I might have found i similar speced one of good quality on AliExpress. It might actually be an original item, not one of the dozens of fake ones (there are many and the product images gives them away easily).
With the new potentiometer in place, the throttle was smooth as butter!
