Is it possible? Has anyone done it?
If we are still reliant on oil for transportation then we are not much better than the cageurs.

It seems like it would be possible, from all the oil-derived parts I can think of:
>chain oil - bio-based lube readily available
>grease - can be made from plant oil and animal fat
>plastic parts - replace with metal or use bioplastics
>tyres - seems like progress is being made here, but I can't find any commercially available 100% natural rubber tyre at the moment