My team is making a 4 motor drive in which 2 of the front motors are geared so it effectively creates a drive on 6 of the wheels.
The issue is the geared systems are such that the motor is in the middle of the two wheel gears (see photo attached). When we added a 4 motor drivetrain to VEX v5 block code, we cannot get the drivetrain to turn properly as when the back motor is going forward, the front motor is going forward but turning those wheels backward so it fights itself. How can we fix this. You can’t tell the system what motors are forward or backward when you do the 4 motor drivetrain.
What else could we do in this situation? My team is young and has very little coding experience (as do I).
Thank you
this would not work because the back wheels are spinning at a different speed to the front wheel, you geared down the back 2 wheels (slowed down the motor) but kept it direct on the front wheel, effectively having your wheels spinning at different speeds
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if you need any help with the coding, feel free to reach out. 
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From what I can see, you have multiple building learning experiences. For starters, the idler gear (the gear in between the two front wheels) is a different size. This is creating a gear ratio of around 1:2, meaning the front two wheels are spinning at twice the speed of the rear wheels. To resolve this, ensure that all three gears are the same size.
Second, the gearing causes the direction of the wheels to reverse. I’m assuming that the gear ratio (which makes it faster) is causing it to lose a lot of torque, which allows the motor to free spin in the direction of the rear wheel (becoming overpowered). This is why you only notice this while turning.
I would also recommend gearing each side (all three wheels) together to prevent fatigue and overheating on just one wheel, and to distribute the force more evenly.
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As stated above, yes, the back wheels are spinning faster than the front.
Furthur, from what i can see from your post, and the image, the code thinks it is driving both motors in the same direction of rotation (as the v5 drivetrain should) but the gears in the back cause the wheels in the back to turn in the wrong direction.
it would be a idler gear if it was just there to connect the wheels via a geartrain, but due to it having the motor attached to it, its just a driven gear. try to use proper or at least accurate terminology
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Thanks for the input 
I was trying to simply explain it as simply as possible and could not think of the correct wording.
