I've got about 45 miles on it now, and I've suffered 2 failures. Yesterday I was going for a ride and got about 50 yards from the garage and the tensioner wheel fell off. I was just starting the motor at the time so I was going slow. I thought something was wrong, and looked down and noticed the power side chain was loose, but it hadn't fallen off the sprocket. I was able to retrieve the star wheel and spacer just laying in the middle of the street, not far behind me, but I couldn't find the screw. I take blame for that failure. I guess I didn't tighten it enough.
The second failure wasn't my fault. I've never had a problem with pedal side before, but tonight I did. I was riding across town, and was about 7 miles away. As I was starting to pedal away from I light, suddenly I felt the chain slip on the pedal side. That was big suprise to me, because it's never happened before. I stopped and looked at the chain. Nothing? I tried it again, and it slipped again. I was thinking this is crazy, that can't happen it the chain isn't loose, can it? Well it was happening. WTF!! At that point I decided to turn around and head home without trying to pedal much. I got about a half mile and the pedal chain fell off. What the f in%$^&@# I rolled onto the sidewalk to take a closer look. I had a flashlight, an allen wrench, a 10mm open end, and a phillipshead screw driver, and a plastic coated cable lock.
What I found was that the rear pedal chain sprocket had fallen off the hub. Close inspection revealed that this sprocket is held on by a threaded ring, that came unscrewed. The rear hub is a cheapy Shimano E110 clone. I thought it was exactly like the other ones I have on my other bikes, where the sprocket is held on by a wire clip in a groove. A foolproof method that never fails. That's why I wasn't concerned with it, and didn't give it any attention. Big mistake.
so now I'm 6 1/2 miles from home, and I can see what the problem is, but I can't get my fingers in there to the threaded ring to screw it back on, because the frame is in the way. I tried for about a half hour to get the ring screwed back on using the phillipshead, and allen wrench, but that got me nowhere. So what I did was push the sprocket into place, and I used the plastic coated cable lock to wrap around the in between the sprocket, and the frame. It was just tight enough fit to hold the sprocket in place and keep the chain on. I still couldn't pedal it, but I could motor it home, and just paddle it away from stops with my feet. That's how I made it home. You got to love dual independent drive.
I don't have the special tool to tighten the ring on, so I'll have to use the old hammer and screwdriver method. I'm going to red locktite that sucker.