- Mon Sep 25, 2017 1:54 pm
(A) I don't see an integrated cooling fan in the picture. You do NOT want to use a motor without a cooling fan.
(B) You CAN remove the stock pinions using a piece of 1/8" steel plate with a slot cut in it. The slot should be ~4mm wide -- just wide enough for the motor shaft to pass through it. The plate goes between the pinion and the motor, then put the plate on a supporting surface (I use my vice just to hold it up), then use a punch to tap the shaft of the motor back through. This is a bit hard on the bearings in the motor but usually I'm throwing that away so I don't care.
To reinstall on a motor that has a smooth shaft, I recommend roughing up the shaft (I use the teeth in my vice to 'emboss' it) until it takes some force to install, and then use a very small amount of red Loctite or other sleeve retainer. I haven't had any failures so far on the 5 motors I've done this on, and it allows you to use the odd-sized gears, like the 15/17/23T ones (that are the same OD as 16/22T standard 32dp pinions).
As for motor selection: Don't get a 7.2V motor. Most of the stock motors are running 13-16k RPM, so if you want a mild speed increase without having to run 18V, find one that runs 20-23k RPM @ 12V. Jameco sells a good 23k RPM one -- look in the Motor Database Sticky.
F-150 - 24-36V with homebrew 100A variable-speed motor controller, 4x 775 motors (no, it's NOT all-wheel-drive--look up 'quad damage' in the gearbox section for more info!)
Princess Mustang - 24/36V, 4x 775 motors, awaiting a speed controller....
Hurricane - 24V w/50A step-down controller, 775 motors