Clutch and old Vex

Vex Clutch 276-1098

Is this clutch a bi-directional one? Can the drive motor go either direction and expect engagement?

And then if the motor is not driving, is the other side free to rotate on its own?

I REALLY wish I could find one or two of VEX Motor Kit [DISCONTINUED] $19.99 Model: 276-2163, which is a continuous rotation (360 servo with built-in/on clutch. Does anyone know if there is a 360 deg replacement. The one listed as a replacement on the Vex web site is not continuous rotation.

  1. Are there adapters that will adapt this square shaft in the clutch to a stepper motor (5MM shaft, with flattened sides - standard for stepper motors). Where would I see those to select & order?


Thanks for the questions,

  1. The VEX clutch is designed to protect motors or other mechanisms from significant shock loading. The clutch’s input is directly linked to it’s output
    unless a large torque is applied to the input or output; this will cause the clutch to slip (the input/output will rotate with respect to each other). If the motor is not driving, the output of the clutch will not be free to rotate.

These clutches were designed for use with the original VEX Motor Kit and the 3-Wire Servo, to protect their plastic internal gears. The VEX 393 motors have steel internal gears so clutches are not required during typical usage.

The VEX Motor Kit has been discontinued, and was not a continuous rotation servo - it was simply a motor with a built in motor controller - without additional sensor, the motor did not “know” it’s speed or position.

  1. VEX does not sell any adapters like you are describing.

Please let me know if you have any further questions,

Thanks Charlie,

OK If I were to use 2-Wire Motor 393 w/ Motor Controller 29, and then power were removed, would there still be some ability for the shaft to rotate without damaging any gears (not fast, btw, but maybe 5 RPM), or would that motor essentially be locked?


How slow can I get this motor to rotate? Is it all PWM stuff?


The motors are not “locked” when they are not being driven, so it is possible to backdrive them with a small amount of torque.

The slowest you can get the motor output to rotate is dependent on the load that is applied to them. With no load, they can rotate at just a few RPM.

Yes, the motor controllers are driven using a 5v PWM signal.

Please let me know if you have any further questions,