34 • E-REVO VXL BRUSHLESS
TQ
i
ADVANCED TUNING GUIDE
Your Traxxas transmitter has a programmable Multi-Function knob
that can be set to control various advanced transmitter functions (set to
Traxxas Stability Management (TSM) by default, see page 16). Accessing
the programming menu is done by using the menu and set buttons on
the transmitter and observing signals from the LED. An explanation of
the menu structure follows on page 37. Experiment with the settings and
features to see if they can improve your driving experience.
Steering Sensitivity (Exponential)
The Multi-Function knob on the TQi transmitter can be set to control
Steering Sensitivity (also known as exponential). The standard setting
for Steering Sensitivity is “normal (zero exponential),” with the dial full
left in its range of travel. This setting provides linear servo response: the
steering servo’s movement will correspond exactly with the input from
the transmitter’s steering wheel. Turning the knob clockwise from center
will result in “negative exponential” and decrease steering sensitivity by
making the servo less responsive near neutral, with increasing sensitivity as
the servo nears the limits of its travel range. The farther you turn the knob,
the more pronounced the change in steering servo movement will be.
The term “exponential” comes from this effect; the servo’s travel changes
exponentially relative to the input from the steering wheel. The exponential
effect is indicated as a percentage—the greater the percentage, the greater
the effect. The illustrations below show how this works.
Normal Steering Sensitivity (0%
exponential):
In this illustration, the steering
servo’s travel (and with it, the
steering motion of the model’s
front wheels) corresponds
precisely with the steering wheel.
The ranges are exaggerated for
illustrative purposes.
Decreased Steering Sensitivity
(Negative Exponential):
By turning the Multi-Function
knob clockwise, the steering
sensitivity of the model will be
decreased. Note that a relatively
large amount of steering wheel
travel results in a smaller amount
of servo travel. The farther
you turn the knob, the more
pronounced the effect becomes.
Decreased steering sensitivity may
be helpful when driving on low-
traction surfaces, when driving at high speed, or on tracks that favor sweeping turns
where gentle steering inputs are required. The ranges are exaggerated for illustrative
purposes.
Throttle Sensitivity (Throttle Exponential)
The Multi-Function knob can be set to control Throttle Sensitivity.
Throttle Sensitivity works the same way as Steering Sensitivity, but
applies the effect to the throttle channel. Only forward throttle is
affected; brake/reverse travel remains linear regardless of the Throttle
Sensitivity setting.
Steering Percentage (Dual-Rate)
The Multi-Function knob can be set to control the amount (percentage)
of servo travel applied to steering. Turning the Multi-Function knob
fully clockwise will deliver maximum steering throw; turning the knob
counterclockwise reduces steering throw (
Note:
Turning the dial
counterclockwise to its stop will eliminate all servo travel). Be aware
that the steering End Point settings define the servo’s maximum
steering throw. If you set Steering Percentage to 100% (by turning the
Multi-Function knob fully clockwise), the servo will travel all the way to
its selected end point, but not past it. Many racers set Dual-Rate so they
have only as much steering throw as they need for the track’s tightest
turn, thus making the model easier to drive throughout the rest of the
course. Reducing steering throw can also be useful in making a model
easier to control on high-traction surfaces, and limiting steering output
for oval racing where large amounts of steering travel are not required.
Braking Percentage
The Multi-Function knob may also be set to control the amount of brake
travel applied by the servo in a nitro-powered model. Electric models do
not have a servo-operated brake, but the Braking Percentage function
still operates the same way in electric models. Turning the Multi-Function
knob full clockwise will deliver maximum brake throw; turning the
knob counterclockwise reduces brake throw (
Note
: Turning the dial
counterclockwise to its stop will eliminate all brake action).
Throttle Trim
Setting the Multi-Function knob to serve as throttle trim will allow you
to adjust the throttle’s neutral position to prevent unwanted brake drag
or throttle application when the transmitter trigger is at neutral.
Note
:
Your transmitter is equipped with a Throttle Trim Seek mode to prevent
accidental runaways. See the sidebar for more information.
Starting Over:
Restoring Factory Defaults
When programming your
TQi transmitter, you may feel
the need to start over with
a clean slate. Follow these
simple steps to restore the
factory settings:
1. Turn the transmitter off.
2. Hold both MENU and SET.
3. Turn the transmitter on.
4. Release MENU and SET.
The transmitter LED will
blink red.
5. Press SET to clear settings.
The LED will turn solid
green and the transmitter
is restored to default.
Throttle Trim Seek Mode
When the Multi-Function knob is
set to throttle trim, the transmitter
remembers the throttle trim
setting. If the throttle trim knob is
moved from the original setting
while the transmitter is off, or while
the transmitter was used to control
another model, the transmitter
ignores the actual position of
the trim knob. This prevents the
model from accidentally running
away. The LED on the face of the
transmitter will rapidly blink green
and the throttle trim knob (Multi-
Function knob) will not adjust the
trim until it is moved back to its
original position saved in memory.
To restore throttle trim control,
simply turn the Multi-Function
knob either direction until the LED
stops blinking.
Turning Range
at Transmitter
Effective Turning
Range on Model
