16 • REVO PLATINUM EDITION
Tuning The Sealed Gear Differentials
Revo’s front and rear gear differentials allow the left and right wheels to
spin at different speeds while turning so that the tires do not scuff or skid.
This decreases the turning radius and increases steering performance.
The performance of the front and rear differentials can be tuned
for different driving conditions and performance requirements. The
differentials are filled with silicone differential fluid (oil) and are sealed
to maintain consistent long-term performance. Changing the oil in
the differentials with either lower or higher viscosity oil will vary the
performance characteristics of the differentials.
Changing to a higher viscosity oil in the differential will reduce the
tendency for engine power to be transferred to the wheel with the least
traction. You may notice this when making sharp turns on slick surfaces.
The unloaded wheels on the inside of the turn have the least traction and
tend to spin up to extremely high rpms. Higher viscosity (thicker) oil causes
the differential to act like a limited-slip differential, distributing more
equal power to the left and right wheels. Revo will generally benefit from
higher viscosity oil when climbing, rock crawling, or racing on low traction
surfaces.
Note:
Heavier oil will allow power to be transferred even with one
or more tires off the ground. This can make the vehicle more likely
to overturn.
From the factory, the front differential is filled with SAE 50,000W oil and
the rear differential is filled with 10,000W oil. The center differential is filled
with SAE 500,000W oil. For the best center differential performance, only
use the 500,000W diff fluid. This viscosity provides the best balance for
acceleration and handling. Power will be more equally distributed to the
front and rear differentials. Lighter viscosity center diff fluid may increase
the tendency for the front tires to be over-driven (spin faster than the rear
tires). Over-driving the front tires will reduce handling and acceleration
authority. Only use silicone differential fluid (oil) in the differentials. Traxxas
sells a range of oil viscosities (see your parts list). The differentials have to
be removed from the vehicle and disassembled to change/replace oil.
DUAL SERVO STEERING SYSTEM
Revo uses dual-servo steering and a single heavy-duty servo saver for
powerful, responsive steering. To prevent unnecessary receiver battery
drain it is important to make sure that the servos are “at rest” when the
steering is at neutral. If one servo is out of adjustment, then both servos
will work against each other, fighting to find center.
Adjusting The Steering System
1.
Remove the servo horns and steering links from the servos.
Disconnect the steering links from the servo saver.
2.
Adjust both the steering links to be the exact same length (41.8mm -
use “Steering Servo Horn Link Length Template” below to set length).
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 saver arm and
the other end to the servo horn
6.
Position the steering servo saver arm
perpendicular to the centerline of the vehicle.
7.
While holding the steering servo saver arm
in the position mentioned in step 6, install
the servo horn onto the servo such that the
steering link is parallel with the centerline
of the vehicle. This will automatically set the
servo horn at the 7-degree offset shown in the
illustration.
8.
Install the second servo horn on the other side
following the same procedure.
If necessary, fine-tune the length of the second steering link to eliminate
any load on the steering system in the neutral position.
If you are using aftermarket servos, it is important to use servo horns
designed for Revo. Optional steering servo horns are sold separately for use
with non-Traxxas servos.
Servo Saver Tuning
An optional stiffer spring is available for the servo saver when using servos
with metal gear sets (see parts list for details). Do not use this spring with
standard Traxxas high-torque servos.
BRAKE SETUP & ADJUSTMENT
Revo is equipped with front and rear disc brakes. The brakes are preset at
the factory and should not require attention. As the brake material wears,
future adjustments may be necessary.
Brake Shoulder Screw Adjustment
The two shoulder bolts that are
used to secure the brake pads to the
transmission housing may need to
be adjusted periodically as the brake
material wears down. They should be
tightened so a 0.50mm (.020”) gap
exists between the disk and the brake pad (on the transmission side).
Adjust in one of the following ways:
1.
Use a .50mm feeler gauge between the brake pad insert and brake disk.
2.
Push the outer brake pad firmly against the inner pad with your finger,
sandwiching the brake disk between the brake calipers. Tighten the
brake shoulder bolts until they just barely touch the brake pads. Do not
over tighten these fasteners or you could damage the brake calipers.
Loosen each of the shoulder bolts by 1 turn.
Brake Linkage Adjustment
When correctly adjusted, the brake linkage
spring should barely touch the rod guide
when the servo is in neutral position (closed
throttle). This will ensure no brake drag
during operation of the vehicle. The brake
adjustment knob can be threaded away
from the spring for less braking power
if desired. Do not adjust knob to apply
pressure against the spring while the
servo is in the neutral position. This will
induce brake drag and cause undesirable
handling.
The position of the z-bend from the
factory is the middle position of the servo
horn for the front brakes and in the rear
position for the rear brakes. Changing this
position will affect the way the brake force
is applied. The brake adjustment knob will need to be readjusted if this
position is changed.
Steering Link Length Template
41.8 mm
0.5mm
gap
Front of Truck
Less Brake
Brake
Linkage
Spring
TUNING ADJUSTMENTS
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