MAXPlanetary System Kit


The MAXPlanetary System is a cartridge-based modular planetary gearbox designed from the ground up for NEO-class motors. The design of the MAXPlanetary has been carefully optimized to provide torque density unavailable in FRC up until now.

The MAXPlanetary System is intended for use with the NEO Vortex Brushless Motor, NEO Brushless Motor, Falcon 500, Kraken X60, and CIM motors. It also supports NEO 550 and 775 size motors (775pro or AM RedLine). Building on the ability to iterate and adjust designs easily, the MAXPlanetary System consists of lubricated cartridges allowing for swapping gear ratios on the fly and with ease. Users can configure a single-stage planetary using one of three different reduction cartridges or build multi-stage gearboxes through stacking individual cartridges together. The user can use the included 1/2in hex shaft or use a custom length of hex shaft best suited for the application. The gearbox also provides two mounting options, face mount and side mount, for ultimate flexibility in your robot design.

The MAXPlanetary Base Kit (REV-25-2109) is the entry point into using the MAXPlanetary System. This kit includes a universal input stage, 1/2in hex socket output, hardware pack, 8mm keyed input coupler kit, and a 1/2in rounded hex shaft. Select a gear ratio kit to determine the right amount of torque for the application at hand. Add a NEO Brushless Motor (REV-21-1650) or an adapter kit if you want to use a different motor, like the new MAXPlanetary Falcon Spline Input Coupler (REV-21-2124) or MAXPlanetary Kraken X60 Compatible Input Coupler (REV-21-2138).



  • Gearbox Dimensions:
    • 0-Stage: 1.500in
    • 1-Stage: 2.000in
    • 2-Stage: 2.500in
    • 3-Stage: 3.000in
    • Height: 2.000in
    • Width: 2.438in
  • Weight:
    • Base kit (no shaft): 261g (0.576lb)
    • 3:1 gear stage: 155g (0.342lb)
    • 4:1 gear stage: 133g (0.294lb)
    • 5:1 gear stage: 138g (0.303lb)
    • 3in Output Shaft: 27g (0.059lb)
  • Exact Gear Ratios:
    • 3:1 Stage: 3:1
    • 4:1 Stage: 4:1
    • 5:1 Stage: 5:1
  • Gear Pitch: 0.65 Module
  • Pressure Angle: 20°
  • Ring Gear Tooth Count: 72
  • Face Mounting Pattern: #10-32 on a 2in Bolt Circle
  • Output Socket: 1/2in Hex, 0.438in Deep
  • Included Shaft: 1/2in Hex, 3.000in Long

Static Load Ratings

The following torque measurements are for a static load condition (i.e. not moving).  The torques listed are for the output of the stage.

  • 3:1 Cartridge - Tested to 290Nm [2567in*lbs] (no failure)
  • 4:1 Cartridge - Fails at 270Nm [2390in*lbs]
  • 5:1 Cartridge - Fails at 240Nm [2124in*lbs]
  • 1/2in Hex Socket Output - Fails at 250Nm [2213in*lbs]

NOTE: Cantilevered (sideways) load on the output shaft puts additional stress on the gearbox and will reduce the torque the gearbox can take.  In addition, shock loads can cause the gearbox to fail in situations where the steady-state torque is still within allowable limits.

Allowed Stage Configurations

The following chart shows which gear cartridge configurations are allowable with different motors.  Cells shown in GREEN are allowed and cells shown in RED are not allowed.

These ratings are based on the default current limit on the SPARK MAX (or Talon FX).  Increasing the current limit increases the maximum torque the motor can produce and may put components of the gearbox outside of their load rating.

 MAXPlanetary Gear Ratio Ratings Table

Kit Contents

Base Kit (REV-25-2109):

  REV-21-2104   MAXPlanetary 1/2in Hex Socket Output   QTY 1 
  REV-21-2106   MAXPlanetary Universal Input Stage   QTY 1 
  REV-25-2107   MAXPlanetary Hardware Pack   QTY 1  
  REV-21-2108   MAXPlanetary 8mm Keyed Input Coupler Kit   QTY 1 
  REV-21-2813   1/2in Rounded Hex Shaft, 3.0in Long, Tapped   QTY 1 

Gear Ratio Kits: *each ratio kit includes a combination of the following cartridges

 REV-21-2101  MAXPlanetary 3:1 Cartridge
 REV-21-2102  MAXPlanetary 4:1 Cartridge
 REV-21-2103   MAXPlanetary 5:1 Cartridge

Product Add-on Options *the following items may or may not be included based on your product selection

MAXPlanetary 775 Input Kit (REV-21-2118):

  REV-21-2116  MAXPlanetary Universal Motor Input Spacer   QTY 1 
  REV-21-2118  775 MAXPlanetary Shaft Adapter   QTY 1 
 M4 x 12mm Socket Head Cap Screw   QTY 2  

MAXPlanetary 550 Input Kit (REV-21-2117):

  REV-21-2116  MAXPlanetary Universal Motor Input Spacer   QTY 1 
  REV-21-2117  NEO 550 MAXPlanetary Shaft Adapter   QTY 1 
 M3 x 10mm Socket Head Cap Screw   QTY 2   


  • As of 11/14/2022, MAXPlanetary Base Kits (REV-25-2109) will ship with an updated MAXPlanetary 8mm Keyed Input Coupler Kit (REV-25-2108). The input coupler kit was adjusted to be slightly shorter so that the CIM, Mini CIM, and Falcon no longer require the shim plate. As a result, the MAXPlanetary CIM/Falcon Spacer (REV-21-2119) is no longer included in the MAXPlanetary Base Kit.
  • Please note that using a 1:1 (no cartridge) requires modifying the length of the motor shaft for the NEO 1.1, Falcon 500, and Kraken X60. A single cartridge reduction setup will still require modifying the Kraken X60 shaft to prevent damage to your motor.


CAD & Drawings