Human powered chaff cutter from bike parts

Lately I have been chopping up scrap bikes to make things that are not bikes.
Mostly carts, but my roving mind is returning to the idea of a human powered chaff cutter made from bike parts.
I happen to belong to a bike coop/community garden,so the idea of shedding soft foliage with human power is kinda irresistible a
My idea is basically a bicycle drive wheel with concrete cast in between the spokes, to make it into a fly wheel.

To that  I want to add blades, an anvil or edge for them to cut against , a feed shoot and a safety guard.
Seating for the operator should allow intermittent pedaling and feeding of "chaff" without having to get off the saddle.

I think the bike wheel/fly wheel idea is pretty sound, but the best way to turn that into something that shreds is still in question.

Right now I'm leaning towards a chute delivering plant matter to right to the flywheel,and  a vee shap blade mounted at the end of the chute   and sections  of angle iron  mounted perpendicularly on the rim of the fly wheel.

Hey, William,

Did this idea ever go anywhere?

My sister had this picture in one of her albums. Not exactly what you're looking for, but I thought you'd appreciate it!

I've seen a bike re-purposed as an exercise bike/spinning wheel.
As I remember the pedaling supplied the turning of the spinning head via a couple of pulleys - sorry the details escape me, but I can try to find the magazine if there is more interest.
A this stage I reckon I'd run out of puff before getting much yarn made

Well, I did fill a drive wheel with concrete, and I still plan on using it.
The only other bike specific thing I still plan on using is the chain.
This is because I am ditching the pedaling action in favor of a treadle action.
Here's a thread that describes some of the evolution of my thinking :
https://permies.com/t/207150/permaculture-upcycling/Bicycles-angle-grinders-flexible-shafts#1729535

William Bronson wrote: This is because I am ditching the pedaling action in favor of a treadle action.

Depending on what you're trying to run, treadles have a lot of benefits.

When a person's pedaling, each of their hips is moving alternately, which shifts the position of the upper body.

When a person's using a treadle, one hip is anchored to the ground, so the affect on the upper body is quite different.