The Fat Tire DJ Bike should work for the wet plate project. I put it together and drove it about the last 2.days. I will need to custom build a bike cargo trailer for it. The trailer needs to be is big enough to haul the very heavy 35x35 inch plate holder flat, to help avoid dripping silver nitrate.
You can accelerate the bike from a stop without peddling using the throttle and the 750w electric motor, which will be good for short distance old man plate holder hauls.
Am trying to develop systems that will allow me to make complete ULF ambrotypes across Canada into my 70s.