I rode my road bike 70 miles Saturday. Halfway through the ride, a buddy I visited in the bike shop where he works invited me to join him and another guy for a gravel ride Sunday. I said: "Probably not; my legs will be shot from today's ride."
...but then I remembered that I'd just bought this electric gravel bike. Perfect! I thought I'd take that, and then just work as much or little as I wanted.
Alas, electrical demons reared their ugly heads. The display kept showing 'Err 71' and shutting down the electrics of the bike. I would restart the controller and it would work for a minute, or just a few seconds, then shut down again. I had to abandon the ride 16 miles in. (out of 33) Took the most direct route back to the parking lot and pedaled along unpowered. (11 miles)
I got home and looked into the Troubleshooting part of the manual, and this is the advice Yamaha gives me:
"There is a problem in the eBike Systems. Turn off the power and then turn it on again.
If the problem cannot be solved, have your bicycle inspected by a dealer as soon as possible.
For Er71 - The problem occurs in the battery pack. Remove the battery pack and check the battery capacity indicator lamps on the battery pack."
Those LEDs can tell us what different errors are. Mine just shows a full battery pack.
I did that, checked all the connections and made sure I had inserted the battery properly. No dice.
I wrote to the dealer asking what I should do. I was hoping he might file a warranty claim and get me a new battery. No response yet today. It's a 55 mile drive with Milwaukee in the middle, but I think I'm going to eventually have to make the journey and drop off the crippled bike.
I'm glad I have a couple other eBikes, or it would've been a lot more painful.