Assembly Instructions - Page 7, Step 3
Micro RS4 Main Page | To the Main Assembly Instructions Page
In this step we will attach the motor to the rear axle housing/motor plate and install the housing to the main chassis of the car.
Step 3
First, install the pinion on the motor. Press the pinion on the motor shaft, then press down on the rear of the motor to seat the pinion fully on the motor shaft.
Be careful to not push the pinion on too far. Use the 1.5mm L-wrench to measure the distance between the motor can and pinion. The pinion should be 2mm away from the motor can, so with the wrench you can estimate how far the pinion should be without needing calipers.
If you push the pinion on too far, use side cutters or scissors to apply leverage to the pinion to pull it off.
Put the motor shaft with the pinion installed through the large opening in the motor plate. Make sure the red wire faces to the top, as shown in the picture below.
Install the motor mounting screws with the L-wrench or your 1.5mm Allen wrench. Don't tighten them all the way, you need to set the gear mesh.
To set the gear mesh correctly, use the piece of paper you used in Step 2 to put between the pinion and spur gears. Tighten the lower motor screw almost all the way, and push the pinion gear against the spur gear. Tighten the top motor screw, then the lower motor screw. Remove the paper.
The space between the pinion and spur gear is the proper amount of space that should be there. Rotate the spur gear forward and back with your finger, and remember how much the gear moves. This is "proper gear mesh".
Install the rear axle housing on the chassis. Note which body you have and what wheelbase (WB) measurement it uses (it's shown on the body). Use the mounting holes closest to the front for short (140mm) wheelbase bodies, or the holes in the rear of the chassis for long (150mm) wheelbase bodies. The Viper GTS-R body is a 140mm WB body, the BMW M3 and Nissan Skyline R34 GT-R bodies are 150mm WB bodies. The picture below shows mounting the rear axle housing in the SHORT wheelbase location.
