First - This is a great forum and I’ve learned a lot.
Second - This is not for any FIRST competition, just a hobby vehicle.
Now to the details and questions. I’m building a tracked vehicle that will end up weighing approximately 80lbs. It will have 4" wide, aluminum cleated tracks. Ground contact length of 30". The drive sprockets have a diameter of 3.5". My thought is to drive it with Victor 888s and CIMs (one Victor and CIM per track). For reduction I was going to start with a VEX single speed (3 motor capable - may want more POWER 
) gearbox driving a chain for further reduction (here’s where I would adjust final drive ratio)
- Are the Victors capable of handling a CIM in stall?
- Ratio theoretically required for single CIM to push tank at 15mph (22 ft/s)
- Is two CIMs enough?
- Is driving two CIMs with one Victor just nuts?
Final note, this will see offroad action.