Traxxas Rally 7407 Owner's Manual page 21

Fine Tuning the Shocks
The four shocks on the model influence its
handling. Whenever you rebuild your shocks,
or make any changes to the pistons, springs
or oil, always make changes to them in pairs
(front or rear). Piston selection depends on
the range of oil viscosities that you have
available. For example, using a two-hole
piston with a lightweight oil will, at one
point, give you the same damping as a three-
hole piston with heavier oil.
We recommend using the two-hole pistons
with a range of oil viscosities from 10W to
50W (available from your hobby shop). The
thinner viscosity oils (30W or less) flow more
smoothly and are more consistent, while
thicker oils provide more damping. Use only
100% pure silicone shock oil to prolong seal
life. From the factory, shock oil is set to 50W
in the front shocks and 40W in the rear shocks.
The model's ride height can be adjusted by adding or removing the
clip-on, spring pre-load spacers. Adjust the ride height so that the
suspension arms are slightly above being parallel to the ground.
Observe how your model handles in turns. Proper set-up will add
stability and help prevent spin outs. Experiment with different
springs and shock oils to find what works best for your current track
conditions.
Centering Your Servo
If you have removed the servo horn from your model's steering servo,
or the servo has been removed for service or cleaning, the servo must
be re-centered prior to installation of the servo horn or installation of
the servo in the model.
1. Remove the servo horn from the steering servo.
2. Connect the steering servo to channel 1 on the receiver. Connect
the electronic speed control (ESC) to channel 2. The white wire on
the servo lead is positioned towards the receiver's LED.
3. Turn the transmitter power switch on. Make certain the
transmitter's batteries are no depleted.
4. Turn the transmitter's steering trim knob to the center "0" position.
5. Disconnect motor wires "A" and "C" (see page 10) to prevent the
motor from turning during the next steps. Connect a fresh battery
pack to the speed control and turn on the ESC (see page 16). The
servo's output shaft will automatically jump to its center position.
6. Install the servo horn onto the servo output
shaft. Align the servo horn one spline from
center, as shown right.
7. Check servo operation by turning the steering
wheel back and forth to ensure that the
mechanism has been centered properly and
you have equal throw in both directions. Use
Pre-load
the transmitter's steering trim knob to fine-
Spacer
tune the position of the servo horn so your
model tracks straight when the steering wheel is at neutral.
Adjusting the Slipper Clutch
Your model is equipped with an
adjustable slipper clutch which is built
into the large spur gear. The purpose
of the slipper clutch is to regulate the
amount of power sent to the wheels
to prevent tire spin. When it slips, the
slipper clutch makes a high-pitch,
whining noise. To adjust the slipper,
use the included wrench to hold the
adjusting nut and roll the model forward
to tighten and reverse to loosen.
Place the model on a high-traction surface, such as carpet . Adjust the
slipper so that you can hear it slip for approximately two feet from a
standing, full throttle start. (Learn more about adjusting the slipper
clutch in the sidebar.)
If you have questions or need technical assistance, call Traxxas at
1-888-TRAXXAS
(1-888-872-9927) (U.S. residents only)
BASIC TUNING ADJUSTMENTS
To achieve a good starting
point for the slipper clutch
in this model, remove the
slipper gear assembly from
your model (see page 22 for
instructions) and tighten the
slipper clutch adjusting nut
clockwise until the slipper
clutch adjusting spring
fully collapses (do not over
tighten), and then turn the
slipper clutch nut counter-
clockwise one full turn.
Do not run your model with
the slipper clutch adjusting
spring fully compressed. The
minimum recommended
slipper clutch setting is 1/2
turn counter-clockwise from
fully compressed.
TRAXXAS RALLY • 21