Geared 4 motor drivetrain

Hi. I am wondering if anyone has any good ideas for a geared 4 motor drivetrain to give us a little more torque and strength while also being good speed. We are having a bit of an issue getting up the platform. Our bot is pretty heavy, and we have normal traction wheel in the front, and omni’s in the back. we can change that if anyone has a suggestion for that too. thank you for the help!

5/7 would be a good ratio
60t gear (motor) to a 84t gear (wheel)
Edit: 143rpm


OK. Sense we have them, would you suggest high strength axels, or not?

Dealers choice
Depends if you want to drill holes or not but if you can I would
Bigger axles: more tank bot

Ok. I have just heard that they can cause extra friction, but That could just be a myth. Thank you very much for the help! Also, I am going to guess that this is using high strength gears too?

Yes, use high strength gears for the wheels
If you don’t you might have spacing issues for the omnis
Edit: Use spacers for the Omni to the big gear if you don’t want locking omnis

Ok. Thank you very much for all of the help!

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“axel” = a type of jump in the sport of ice skating
“axle” = a shaft used on a robot


Sorry. Spelling does not compute for my brain right now.

From my understanding (don’t quote me on this), using smaller wheels would also help your issues a bit, it takes less power to spin them so you don’t have to gear down so slow. Additionally, I don’t think you need high strengths in your drive base, if your axles are supported closely on both sides they should persist just fine.

If there’s anything to correct in here, please somebody do.


Ok. Thank you!
20 Char

I have never used high strength axles on a drivetrain before, and I haven’t bent or damaged a standard drivetrain axle either. I feel like high strength would just add more friction and take too much effort for the strength they provide.

Personally, I use a 4 motor (200rpm) chassis with a 1:1 gear ratio, and can easily platform with two neutral goals. It struggles a little with three mogos, but still makes it up. In your case, I don’t know why yours is struggling. Friction is possibly at play here, so maybe check your axle spacing and possibly remove a washer or two. It’s also important to check that your both sides of your chassis are actually parallel. I don’t know wether traction wheels affect platforming or not, but maybe experiment a bit. Another thing to watch out for is your center of gravity. Is most of your robot’s weight low near the chassis, or is it up high? If you have a lift, do you raise it all the way up when you platform? That will raise your center of gravity and increase the chances of tipping or loosing traction on a set of wheels. And finally, this might seem obvious, but don’t run your motors too hot. Let the motors cool down every 10 minutes or so, especially if you’ve been putting a lot of strain on them.


I would personally only use HS axles as a driveshaft to transfer torque across long distances. In a standard gearbox, the LS axles should hold fine as long as everything Is put together correctly



20 characters cha

Do you use regular (green) motors in your drivetrain? What kind of wheels do you have? Do you mind sharing a pic (or even a drawing) of your chassis/drivetrain?

Give me a sec, and yeah I can do that. I use green motors.

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Thst is the old design

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This is what someone suggested