Single Reduction Clamping Gearbox

The Single Reduction Clamping Gearbox achieves versatility through its simplicity. This gearbox uses four bolts to clamp onto a piece of 1" x 2" VersaFrame tube - no precision machining needed. Once mounted, it mounts a CIM-style motor offset from a bearing block on a perfect 84-tooth gear spacing. Use this efficient setup to drive an upper mechanism with ease, or combine multiple gearboxes to create a smooth-running, lightweight VersaChassis.

  • Simple design for quick assembly and maintenance

  • Variety of gearing options

  • Combines with the Plastic Bearing Block for a second stage reduction

SKU: 217-4156

Availability: In Stock


This chart explains the gearing options for the Single Reduction Clamping Gearbox paired with the Plastic Clamping Bearing Block. Refer to the Clamping Gearbox / Plastic Bearing Block drawing for detailed gear spacing.

4" Wheel
Clamping Gearbox Plastic Bearing Block
(Stage 2)
Adjusted Output Speed
14:70 Not Used 15.01 ft/s
(using 14t center distance)
Not Used 13.94 ft/s*
12:72 Not Used 12.51 ft/s*
(using 12t center distance)
Not Used 11.47 ft/s*
14:70 30:66 6.82 ft/s
12:72 30:66 5.69 ft/s
6" Wheel
Plastic Bearing Block
(Stage 2)
Adjusted Output
14:70* 30:66 10.24 ft/s*
12:72 30:66 8.53 ft/s
14:70 24:72 7.51 ft/s
12:72 24:72 6.26 ft/s

The Single Reduction Clamping Gearbox naturally pairs with a Plastic Clamping Bearing Block or VersaBlock to establish a standard drivetrain gear reduction (see the Bearing Block Spacing drawing for details). For those who wish to use a 6" wheel, VEXpro HTD belts & pulleys can be used to achieve the same result. Download the STEP file for this Application Example here.



P/N Description Material CAD Drawings Weight
217-4156 Single Reduction Clamping Gearbox Glass-Filled Nylon Gearbox
Application Example
PDF 0.250 lbs
Additional Info
Kit Contents (1) Single Reduction Clamping Gearbox - Front
(1) Single Reduction Clamping Gearbox - Back
(4) #10-32 Jam Nut Nylock
(4) #10-32 X 1.375" Socket Head Bolt