Chains are really handy for designing a dual mode vehicle, and they are
light weight, very simple, and very efficient. I always heard they are
better than 98% efficient. If you enclose them, the smutty oil problem
goes away and they last nearly forever (even on 100HP+ motorcycles they do
well).
I hope others will correct and or add to this ...
Since diy-ebike-kits have hub style motors that spin the wheel without
involving the chain that could be added to an existing cargo bicycle, I will
assume his chain elimination desire is in the transference of the human
power to the wheels. An ebike
