3.5mm Bullet connectors.
I put the female part Next to the motor. (see attached pic) I solder a wire onto one of the posts/holes. Cut it really short (maybe 1/4" or less), strip the silicone covering off the wire. I then tin that wire and attach the female connector and cover with shrink tubing. I repeat this process for the other 2 posts/holes on the motor.
For the speedo wires, I put the male side of the connector here. I cover the wires A, B, and C with their respective colored shrink tubing to keep things straight.
I've done this for my cars as well as a few other people at the track. It works VERY well and makes swapping out motors easy.
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