As the motor market evolves, we have updated the restricted division rules to allow wider flexibility and options. Many 21k rated motors turn at least 21,500 depending on your track voltage. Some tracks use 3VDC motors rated for 5400rpm, which turn at least 21,600rpm at 12VDC. In light of this, the motor rules have been changed to allow 22,000 rpm rated motors. The motors must still be used stock and unopened.
Slot Car Oval Racing Association 