[Al Skierkiewicz]

Just to add a word of caution, direct drive will require some additional bearing support if you plan on adding wheels to the output shafts. Failure to provide adequate support will increase the bearing friction at the output of the transmission which results in high current and early failure of the bearings. Many teams that use chains forget this point as well. Unsupported side loads, transfer the load to the bearings and internal mechanics resulting in significant wear and friction. The friction is in turn reflected as high current in the drive motor which in turn causes excessive heat.