Freewheel systems: redundant in mid-drive machines?

As I work through my hub issues, I've been thinking dangerously.

Is the ratchet system in our rear hubs redundant to the ratchet or similar engagement system that many mid-drive bicycles appear to implement? Without trying to clumsily recreate from first principles the rationale behind a rear freewheel or freehub system, does it mechanically matter whether it's in the wheel or in the bottom bracket?

Operationally, not having the chain moving while coasting is nice for one's pants, but what else am I missing?

This is just an occasional problem, but if the clutch in the mid drive motor locks up, and the motor is stopped while coasting still,with no freewheel in the back the rear wheel will still keep driving the chain, but it will droop in-between the BB and rear wheel, tangle up, and keep going until the rear derailleur is stretched all the way and rips off the frame.

Its totally different than a one speed, fixed chain length with tensioner set up mid drive. Then the chain is so tight it will drive the whole motor around even with a locked clutch (hopefully), and not go spilling off to the side of the front sprocket until it jams.

Voltron said:

This is just an occasional problem, but if the clutch in the mid drive motor locks up, and the motor is stopped while coasting still,with no freewheel in the back the rear wheel will still keep driving the chain, but it will droop in-between the BB and rear wheel, tangle up, and keep going until the rear derailleur is stretched all the way and rips off the frame.

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Certainly, that's what we see in any other traditional BB bike with a derailleur and the freewheel fails or the chain gets caught in the spokes - goodbye derailleur, and maybe chain depending on how fast you're going. One's nose and chin, for that matter, after the superman impression.

If (and that's sometimes a big if) one trusted the clutch in the motor, then it seems redundant. As far as I can tell, motorcycles don't have freewheels, they just have a sprocket and a fixed hub, and depend entirely on the motor's clutch to disengage it.

I wonder why bicycles developed the rear one-way clutch rather than doing so in the hub, aside from the obvious clothing-destruction proclivities.

Schwinn actually had that for a while, freewheeling cranks and fixed rear cluster. It sucked.

Having the chain going around full time coasting down hills wasn't good.

You don't coast much on motorcycles.

The redundancy of the ratcheting freewheels does make sense for safety, but also as it allows full disengagement for the driveline while coasting to reduce noise and wear. There is one minor benefit for the fixed cluster/ratcheting cranks - it allowed shifting via derraileur while the rider was coasting, as the chain was never really coasting.

Voltron said:

Schwinn actually had that for a while, freewheeling cranks and fixed rear cluster. It sucked.

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That wasn't a Schwinn system, though they did use it extensively. That was the Shimano Front Freewheeling system. The rear sprockets were designed not to overrun in normal use, but they did have a slipper clutch inside to allow them to move in case of a jam.

The intention of the system was to allow normies to shift whenever the bike was moving, rather than only when pedaling. It was often paired with Shimano Positron, a push-pull cable shifting system that was one of the first mass market index shifters. I argue that these systems didn't suck when compared to other less innovative bike transmissions in the same time period and price range. In fact they were a huge improvement over the Schwinn Sprint (Huret Allvit) derailleur system that preceded them in the Schwinn lineup.

My biggest beef with Shimano FF is that the big steel chainring/guard assembly serves as a resonator and makes the front ratchet obnoxiously loud. We didn't see (hear) other ratchets that loud until rackety freehubs came into fashion in this millennium.