Mobile goal lift not strong enough

We are having issues with our lift because the motor is not strong enough to lift the goal. We got the goal to work but it wont lift a goal.

This is what we originally built. We have tried multiple different things but nothing has worked.

I recommend a high torque motor cartridge linked to a 12/84 torque gear ratio (12 tooth metal gear to a 84 tooth high strength gear) and a better motor mount. Should work fine (I’ve tested it before)
please use bearings


It appears your pinion is cantilevered, I would recommend otherwise as this is what drives the main gear. I would recommend you build a sturdy gearbox, and improve the build quality of the entire mechanism as a whole. Here are some of my tips for build quality ;

  1. Bearing Flats wherever you have a joint, regardless if it’s a screw joint, especially if it’s an axle.
  2. Square your metal so that it is perpendicular to one another. I use the new single screw V5 bearing flats as a method for alignment, it has a square protrusion
  3. Box the metal that is under extreme strain to prevent folding. You can accomplish this by placing spacers in the C-Chanel when connecting two pieces of metal.
  4. I usually use a tape measure to make sure that the beginning of a mechanism is not wider or smaller than the end of it. You add undue friction when a mechanism is not properly aligned.

I have attached an image of our mobile goal lift, take note of the gearbox and the c-channels. I hope this helps, please let me know if you have any questions.


We don’t have the 84 tooth gear. We won’t have enough time to order it before our first competition .


You can put two standard 84T gears back to back and get similar results. For extra peace of mind, bolt them together.

You can make almost any gear ratio and motor combination to work for a mobile goal. There are certain caveats that come with this idea, namely speed and amount of rubberbanding neccesary. A 1:5 ratio with one motor will work fine, but you need to build a better gearbox, and decrease the amount of friction within your mechanism. You seem to have enough space to use your chassis as a gearbox. Since you are using one motor, I would brace your mechanism with a bar across.


Make sure you are using the red cartridge, your motor need to be straight, and try to make it so the mobile goal is close to the motor. You need as much leverage as possible. Also, please use bearings, and tie the two side together with a c-channel or something like that.

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