Lance, I will email you a few pictures of my new heavyweight and its drive setup. I used a combination of spur gears and sprockets and chain to firstly gear down and then secondly to transfer the drive from the rear wheels to the front.

Sprockets work a treat but you have to line them up correctly.

Never attach a wheel directly to a motor. You always have to gear the wheel down so that the wheel rotates with less speed but more torque.

When it comes to attaching a wheel or sprocket to a shaft there are a number of options available. What weight class are you looking at building in?

I would not recommend either the middle or light as there are so few robots around in these classes (if any). I would recommend you start off with a featherweight (12kg) and then look to something bigger.