Couldn't 'bike' the shredder

I am experimenting with human energy to shred… I fail. Now I must do more saving while am looking for a 2KW 70RPM dynamo. =D

You have the gearing the wrong way around. You want to use the small sprocket on the bicycle crank and a big sprocket on the shredder (as big as you can find). That will work much better.

Halo pak,
Coba tetap pakai pedal sepeda, hanya perlu ubah sedikit. Rantai tidak langsung tersambung dengan as shredder, gunakan gear untuk memperkuat dan memperbanyak putaran. Buat yang ahli mesin mungkin bisa menghitung seberapa banyak gear yang digunakan beserta ukurannya.

It will never work, it’s just physics and numbers, a good cyclist can give 250w for a long time, till 400 for a while, if you have a reduction ratio 1:3 or 1:4 (48/16 or 56/15) this would be not enough and in add you say you want to put the shredder in the rear axel so it will be impossible with a ratio of 4:1 or 3:1 so the only way I think it could work is putting the shredder axel in the big wheel and add a lot of balanced weight on the rear wheel with a multi speed gear, than using other bicycle to spin… It means use 2 bicycle instead that one put them together from the back and make a frame… Something like this.

I really think this idea holds promise. I know the version 2 link has no bike components, but I think this is definitely possible. To those thinking about doing this: I wouldn’t go with building the frame from scratch to start, but just modifying an old used bike bought for cheap could be relatively easy.
I am going to try to buy just the shredder box and then attempt to mount the axle of the shredder box to the rear chain ring from a bicycle in its normal position; I will be using a single speed bike for simplicity.

Very good job, but as mentioned, I would make some little changes:
– The gearing in the other way round (the bigger one in the shredder, the smaller one near your feet.
– The bigger one has to be even more big. You need a 1:5 ratio (at least)
– You could add a Flywheel in order to create a ‘momentum’ during the shred; if you don’t, the shredder could jam frequently.

Not a change, but a question for everyone that can help. Is that chain tight enough? I am not sure, but it seems to me that it is loose.


Making a few changes to your design is all you need. Just have a look at this topic for more info:

Really nice machine Well done !
and yes ! it could be functionnal with wheel sizes inverted !

I’m going to build the same one !