My similar Lafree Twist, not as strong as the Kalkhoff in some respects, did 4.5 years of very tough service with me in a very hilly area, and it included towing my very big trailer with large loads two or three times a week as you see it in
this photo.
Then I sold it to forum member aaannndddyyy who has used it for the best part of another year so far. I recelled the battery sold with the bike at 4 years, but the second battery which wasn't recelled I passed to another forum member who uses it as a range extender. That has the original cells at well over 5 years old.
All I did on the Lafree apart from changing the hub gear when I first bought it was to fit a Marathon Plus rear tyre and new brake pads when they'd worn out.
The very heavy towing wrecked the gearhub after 4 years of that abuse, but a new insert put that right. That wouldn't apply in your case of course.
In general, Panasonic motor bikes are running from when they were first introduced 7 years ago. The earlier power unit had a couple of bugs which resulted in a small number failing, but the new unit has attended to those so will probably be very reliable.
As for other e-bikes, the hub motors in general have been very reliable, even the cheapest ones on Chinese shopper bikes long outliving the cheap bikes they were sold in, and they appear second hand for those who want to use them as kit motors.
The best lithium batteries now arriving will probably have a life of around three years, depending on use.
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