It was a total loss in my case, before I knew what was happening the derailleur was wrapped around the spokes and the chain badly twisted and bent. All just fit for the bin. I didn't have any tools on me (typical, they were on the other bike back home) and I couldn't even get the chain "quick release" link to release. Had to tie it all up out of the way as best I could with string and let the hub get me home. I was in the middle of nowhere, miles from home with no phone signal. So I couldn't even have called for help. It's not a common occurrence, but when it does happen it can be catastrophic. Chain failures have been more common, but I replace my chain at least once a year these days.Hi @WheezyRider - I have had a rear mech fail on a long cycle camping tour somewhere in the Portuguese outback - I'm still not sure how or why it happened but the chain jammed in the RM and it was bent out of shape and rather than risk breaking the rear hanger, I took it off.
This left me with a long chain which I shortened using a chain breaking tool with the chain running off the middle sprocket and middle chain ring which was enough to get me to a town with an LBS and a new rear mech and chain
Oh, and I noticed back in post 100 that you said
I was really suprised to read of your experience with a mid drive - I have a TSDZ2 on two bikes and to me they feel very natural to such an extent that I forget that I'm powered by the motor at all until I turn the assist level down or off. If you live anywhere near the Portsmouth area, I'd be pleased to let you have a test ride as I really cannot fathom out why the ride you'd had felt unnatural - was it one of those BBSxx jobbies by any chance?
PS - One of the guys in my local cycling group had to buy another Bosch battery for his Active Line mid drive - £550 it was. He knew I built my own batteries and casually asked me how much my battery cost - when I told him around £80 he went very quiet.
I don't give a fig if the Bosch stuff is more reliable than my Chinese stuff (and I've no complaints so far), as I know that I can if I so wish, rebuild/program just about every part in my ebike system without visiting a mortgage broker or LBS - but each to their own and to be fair, a lot of my local cycle group members have Bosch ebikes and are happy enough (but then I'd never admit to disappointment if I'd spent several £k's on a bike ).
As for how mid drives feel, I think it just shows that what works for one person doesn't work for everyone. Unfortunately, there are certain forum members who have the childish mindset that just because they have an expensive hammer they think every problem looks like a nail.