We have a four motor, eight wheel chassis. Making each side have 2 motors and 4 wheels. One side of this chassis is a gear train that goes as follows: 60t-36t-60t-36t-60t-36t-60t. The four motors are attached to the four 60t gears, with the three 36t gears between them. As of now, we have the two motors driving the first two 36t gears. However, the weight of our robot is distributed evenly, and we’ve been having issues with overheating in short amounts of time. If we were to move the motors to the first and third 36t gears. Would the equal distribution make it faster and have less overheat time. Would it be worth taking the chassis apart? The motors are blue gear cartridges by the way.
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The overheating is most likely caused by friction or high acceleration with low torque. Simply moving the motors is unlikely to fix the issue. The overheating points to a more fundamental problem with the drivetrain.
This could be high rpm gearing causing low wheel torque, a drive with high friction, or a driving style that expects more acceleration and pushing strength from the motors than they can give. (Pushing or resisting pushing is a very quick way to overheat a motor if done for an extended period of time)
May I inquire what colour gearboxes you are using for your drivetrain and the size of your wheels?
Hope this helps. 
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Equally distributing the motors isn’t usually very important. Gears connect all the wheels anyways, so the force the wheels put on the ground will be evenly distributed. The main things to look for when you drive overheats is drive power, speed, and friction.
Most competitive teams have 6 motors on their drivetrains, giving them a lot of torque and making it significantly harder to overheat compared to 4 motor drivetrains. This leaves 2 motors for the rest of the robot, which is fine if you have pneumatics.
Your drivetrain speed seems pretty good, assuming you are on 3.25" wheels. 2.75" wheels would be kinda slow, and 4" wheels would be way too fast and would overheat.
Inefficiencies from friction in your drivetrain and can make it overheat really fast. There should be plenty of resources available on this forum and other places on how to reduce friction in drivetrains, if you do a little sleuthing.
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OP is one of my teammates, and our team came to the conclusion that we were gonna swap to 6m drive once we could accomplish scoring tasks with just 2 motors. I’m not too worried about it, as we decided to swap back to hook because a 4 motor hood was a bit much. We found some stuff on reducing friction, and it all works, but one thing i saw that we haven’t done is leave a small gap on the axles and screw joints. Apparently, the rule of thumb is to leave a fingernail width of space on the axle.
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