I've ridden my new bike about 9 or 10 times since I bought it. At least once per ride, usually as I begin to pedal from a stop, there's a feeling like when the chain slips. It lasts a few seconds and then the pedal assist activates and everything is fine. Up until this morning, that's what I thought was happening.
However, this morning when it happened it wouldn't stop happening. I got off the bike to check the chain and it was fine; full contact with the cassette and crank set. But when I turned the crank set by hand the rear hub/cassette spun freely and wouldn't drive the rear wheel at all, as a regular bike would.
I turned off the pedal assist and battery and the same thing happened. The crank set turned without resistance. (imagine a stationary bike) :( I still had 1km to go to get to work. That's not a big deal, but then I wondered how the hell I was going to get this bike to the store where I bought it to get it fixed.
After 5 minutes of walking it, I decided to get back on the bike and see if I could get it working again. I enabled the pedal-assist and slowly tried to pedal to make the pedal assist activate and that made the cassette finally "engage" and drive the wheel, and I was able to pedal as a normal bike again with or without assist.
Once I got to work I sent the store a message on their web site asking if I could drop it off on the way home today. (Assuming it works well enough to get me there, that is) It was a final sale, since it's actually a used bike, but they did give a 60-day warranty on it. They replied saying they would schedule it to be looked at tomorrow if I dropped it off later today.
One other thing, that is more of annoyance to me, is that the computer will not remember the time after being programmed. I tried replacing the battery in it and that didn't help. I was going to live with that but since this new issue popped up I'm going to get that fixed as well.
I hope this is a one-time thing; I really don't need the stress from this.