A few things which will help with motor life and performance.
- When adding and attaching the motor to your car, I cannot stress enough the importance of using washers under the heads of the attaching screws. Without the washers you risk a loose motor at the most inconvenient time, such as causing a stripped spur gear while leading a race!
- The motor has multiple holes which all may be used to mount the motor to the motor plate. The motor does not care in what position it is mounted, even upside down (that is, the terminals on the bottom). As long as you can safely attach and isolate the 'A-B-C' wires from each other (and attach the sensor wire), the motor will work well. By the way, touching the 'common plate' inside the motor with a mount screw while running is not an electrical problem in TPP motors but may be a mechanical problem (see #4 below).
- Since the motor will work in any position, do not think the motor is 'finished' if you strip the favorite mount hole used to attach the motor. It is important to use two holes (180 degrees from each other) to keep it well mounted (using washers under the screw heads). It may be inconvenient to lengthen the ESC wires or relocate some component but save the motor by mounting in another set of holes.
- Watch the length of the attaching screws holding the motor to motor-plate. In some motor winds, the 'common' connect point inside may be very close to the mount holes; if the screws are too long you can pull the threads out of the motor when tightening not allowing the motor to be torqued properly to retain your pinion to spur clearance. If you do, see #3 above. You can use different thicknesses of washers to get the correct thread engagement.
- I have seen cars with carbon fiber motor mount plates. Carbon fiber is a great weight reducer but a poor heat conductor (an aluminum motor plate will allow better heat dissipation). And in most cases, the carbon fiber plate is thicker, requiring longer mount screws (with washers). And the motors seem to vibrate a little with the CF plate, like it does not retain the screw torque allowing the motor to move more than an aluminum plate. Make sure the screws are tight each race and accept a little extra noise as the CF plate seems to have a resonance in a range we can hear as a 'noisy car' in some situations.
- Fixing stripped holes in motors is difficult for the average car owner. I have good equipment, and it takes a while to setup the tooling to attempt a repair. My best advice: (a) be extra careful when threading the screws to the motor (b) if you have a thread problem with your favorite motor, rotate the motor to get two new holes, and adapt your wiring to use the new position.
A very effective and simple mounting system like this has been used since the 1980's. But it takes many details to be sure it is done correctly for a successful race completion. Good luck with your race program.