I was so enamored by the fact that my creation actually worked, it completely escaped me that it wasn't working as planned. The acceleration and range were on par with a toy. I initially suspected the batteries weren't capable of generating the amps needed. A quick visit to the B-B Battery site shows these 17AH units can do 299A for up to 5 seconds. Pack voltage seemed plenty high after charging: 78.2V
I knew that any one of the components with temporary connections could be suspect. First on the list to correct was the main battery disconnect. Gone is the 30A breaker zip-tied to the wiring panel. In its place is a real battery disconnect switch, mounted in a new aluminum bracket behind the battery tray. Since I don't need access to the wiring panel to flip the power on, I could now ride with the tank on.
I also needed to mount the 400A fuse, rather than suspend it off the contactor terminal. I know there are mounting blocks for these fuses, but why not take advantage of the acrylic wiring panel, and save myself $20. Looks cooler too.
Subsequent test rides still showed something not quite right. Three trips down the street and back later, the bike would barely limp up the driveway, but the pack voltage was still 74V. The best thing I could think of was to pull some data from the controller while riding. This would also give me a chance to tweak the controller settings. Upon connecting the controller to the software, my neglect was evident. The "Under Voltage" slider was was maxxed out, essentially cripling the controller immediately. By hitting the "Defaults" button, reasonable starting values were inserted, but I upped the top speed and Max Output Curent a little just to be safe.
Acceleration is much better and the controller logs show almost 180A. I will need to get some lights wired up ASAP so I can test the range.
Starting to feel like a real motorycyle.
Nice work! That's really clean.
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