Lego Technic Gear Ratios

This is a guide indicating how to Lego connect gears in a way that will work, without as much trial and error. Use these at your own risk, especially under high torque circumstances. The images were made useing LDraw and 'rendered' in MLCad. Special Note must be made to the diagonal combinations, they my wear down the gears quicker because of friction or slipping.

  • Normal Gears are in gray
  • Double Bevel Gears are in black
Gears UsedRatioImageNotes
8 - 12 2/3
0.667
8 - 12 A lot of Friction
8 - 16 1/2
0.5
8 - 16
8 - 24 1/3
0.333
8 - 24
8 - 40 1/5
0.2
8 - 40
12 - 20 3/5
0.6
12 - 20
12 - 24 1/2
0.5
12 - 24
16 - 20 4/5
0.8
16 - 20
16 - 24 2/3
0.667
16 - 24
16 - 24 2/3
0.667
16 - 24 Not as close as it could be
20 - 24 5/6
0.833
20 - 24
24 - 40 3/5
0.6
24 - 40

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