As an alternative to using a smaller pinion than you want, you can make an adapter bushing for the CIM 3/4 boss and make a larger centering hole to accommodate the larger pinion. Of course, you are limited to a max diameter on the bushing by the edge to edge distance between the 10-32 FH screws to mount the CIM. In addition, you should have several CIM/Bushing motors set up so you are not "pressed" to remove a pinion if a swap becomes necessary. By the way, we have never lost a CIM motor, and have done a review of them in the past after a long competition season and post season play, and have never been disappointed in their durability.
