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Predator RPM Disc, 2.0mm Motor Shaft

U/M: Pkg. of 2

NOTE:  Motor shown in product photos is for illustration only - NOT included.  Available for purchase separately.

Predator RPM Disc, 2.0mm Motor Shaft.  For motors with 2.0mm diameter motor shaft (e.g. FC-130, FK-180).  This easy-to-use accessory helps ensure accurate results when measuring motor RPM.

Package contains two (2) 3D printed plastic RPM discs and set screws.


1)  If you are using a given disc for the first time, CAREFULLY thread one of the included set screws into the SIDE hole.  You will need a 1.3mm (0.050") hex key / driver (not included).  Thread the set screw in until you can see the end of the set screw in the motor shaft hole.  Back the set screw out until it is no longer visible in the motor shaft hole.

2)  CAREFULLY insert the RPM disc onto the motor shaft.  The small hub with the set screw should be facing toward the motor (i.e. the flat face of the disc should be facing away from the motor - see accompanying product photo).  Note the shaft will not go all the way through the disc - this is normal.  Do NOT try to force the motor shaft all the way through the disc.

3)  CAREFULLY tighten the set screw until you feel it contact the motor shaft - STOP when the set screw just makes contact.  DO NOT OVERTIGHTEN or you will strip the threads in the plastic hub.

4)  Position and secure the motor so the silver line on the smooth surface of the RPM disc can be "seen" by your contactless tachometer (not included).  Connect your motor to a variable power source (not included).

5)  Remove the disc from the motor shaft by following the earlier steps in reverse order.