Traxxas TRX4 HIGH TRAIL EDITION Owner's Manual page 28

Screw Positions
Spur Gear
39 45
9
- A
10
- B
11 - C
12 - D
13
- E
14 - F
15 A G
16 B H
17
C -
18 D -
19 E -
20
F -
21
G -
22 H -
Stock factory gearing
Does not fit
28 • TRX-4
TUNING ADJUSTMENTS
Adjusting Gear Mesh
Incorrect gear mesh is the most
common cause of stripped spur
gears. Your model includes a fixed
gear positioning system to simplify
the process and ensure proper gear
mesh settings. Access the gears by
removing the three 3x8mm button-
head screws from the gear cover;
remove the gear cover. Remove the
motor/motor plate assembly from
the chassis.
To set the gear mesh, use the chart
to the left to identify the screw
positions on the motor plate (A - H)
that correspond with the chosen
motor pinion (9-T - 22-T) and spur gear size (39-T or 45-T). Remove
the two screws from the motor/motor plate and reinstall in the
corresponding positions; reinstall the motor/motor plate assembly
in the chassis.
Motor Removal/Installation
To access the motor, remove the gear cover by removing the three
3x8mm button-head cap screws. Remove the motor/motor plate
assembly from the chassis; then, remove the two screws holding
the motor to the motor plate. Installation of the motor is the
reverse of removal.
SERVO STEERING SYSTEM
TRX-4 uses a single metal gear servo for powerful, responsive steering.
Adjusting the Steering System
1. Remove the servo horn and steering links from the servo.
2. Adjust the drag link to 133.2mm; adjust the steering link to 77.3mm.
Drag Link
133.2mm
Steering Link
77.3mm
3. Switch on the power to the receiver and the transmitter.
4. Adjust the steering trim on the transmitter to the neutral "0" position.
5. Connect one end of a steering link to the steering servo arm and the
other end to the servo horn.
6. Position the servo horn perpendicular to the centerline of the vehicle
as shown below.
Front of
Truck
If you are using aftermarket servos, it is important to use servo horns
designed for TRX-4. The servo horns must measure 22mm from the
steering linkage mounting hole to the servo mounting hole.