FINAL ADJUSTMENTS
MOTOR GEARING
To get the most from your motor proper gearing is
important. The gear ratios listed in the chart below
are recommended starting gear ratios. Ratios can
vary from track to track but you should not change
the pinion size more than one tooth from the rec-
ommended ratio.
CAUTION! Increasing the pinion size by more
than one tooth can damage your motor from ex-
cess heat.
MOTOR
PINION
SPUR
24° ROAR stock motor
22
81
DS Spec motor
21
81
36° stock motor
20
81
14 turn modified motor
19
84
13 turn modified motor
18
84
12 turn modified motor
17
84
TIRE DIAMETER ADJUSTMENT
If you change tire diameter you can affect your
gearing. You can calculate any gearing adjustments
by using the following formulas.
Old Pinion
Factor
Results New Pinion
Gear
Gear
18
X 1.105 =
19.89 = 20
(round to nearest whole
number)
Old
New
Tire
Tire
Factor
Dia.
Dia.
( 2.1"
÷÷÷÷÷
1.9" )
=
1.105
PAINTING THE BODY
1 While the body is still clear, mark and cut out the
holes for the body mounts and antenna tube.
2 Clean the body and wing thoroughly before paint-
ing with warm water and a mild dish soap.
3 Mask the inside of the body according to your
paint scheme, using automotive masking tape for
the best results. Take the time to press down all
edges of the tape. Mask off the holes you cut with
tape on the outside of the body.
4 Spray the body and wing, applying the paint in
thin coats and letting it dry between coats. We
recommend Pactra paints.
RADIO ADJUSTMENTS
Charge the transmitter batteries if they are NiCads.
(See your radio manual for instructions.) Next
charge your battery pack according to the instruc-
tions included with your battery charger or battery
pack. Make sure all the ESC connections are ac-
cording to the appropriate manuals. Now use the
following steps to make the final adjustments on
your car.
1 Turn the transmitter switch ON
2 Make sure the motor is unplugged or unsoldered.
3 Plug in or solder in your battery pack.
4 Turn the car switch to the ON position. (This is
normally attached to the ESC.)
5 Move the steering control on the transmitter to
the right. Do the wheels steer to the right? If not,
you must reverse the steering servo direction on
your transmitter (see radio manual).
6 After you have the wheels steering in the correct
direction, remove your hand from the steering con-
trol on the transmitter. Now look at the servo horn
mounted on the servo. Is it pointing straight down?
If not, adjust its position with the steering trim con-
trol on the transmitter, or move its position on the
servo.
7 Now look at your front wheels. Are they pointed
straight ahead in relation to the center line of the
chassis? If not, first check the alignment of the
servo saver in relation to the wheels. Do they now
point straight ahead? If not, use the steering tie-
rod turnbuckles to adjust each wheel so that it is
pointed straight ahead.
8 Adjust the ESC (electronic speed control) ac-
cording to the speed control manufacturer’s instruc-
tions. Note: Some manufacturers have the motor
connected during adjustment and some do not.
Now turn the car ON/OFF switch OFF.
9 Plug in or solder in your motor. Place your car on
a block or car stand so that the rear wheels cannot
touch anything. Turn the car switch back ON. Check
the ESC operation and settings. After you have set
and checked the speed control, turn the car switch
OFF.
10 The transmitter switch must always be the
FIRST
SWITCH TURNED ON and THE LAST SWITCH
TURNED OFF.
CONGRATULATIONS! YOUR CAR IS NOW
READY TO RUN!
SETTING THE TWEAK
We set the “tweak” after EVERYTHING ex-
cept the body is installed on the car, including bat-
teries, motor, speed control, and all the radio equip-
ment.
WHAT IS TWEAK? Ideally, the left wheel
should be pushing down on the ground with ex-
actly the same force as the right wheel. If this is
not happening, the car is TWEAKED (or twisted).
This can cause the car to spin out easily under
acceleration. It will also cause the car to oversteer
in one direction and understeer in the opposite di-
rection.
CHECKING THE TWEAK.
1 Measure the front chassis width. Use half of this
measurement to find the centerline of the chassis.
2 Scribe the centerline at the front of the chassis
with your hobby knife.
3 To tweak the car, place the tip of a hobby knife
on the center mark as shown.
4 Lift the front of the car slowly. We want both tires
to leave the ground at the same time. If one tire
leaves the ground before the other one, the car is
tweaked.
CORRECTING THE TWEAK. Loosen the T-
bar tweak screw 1/8 of a turn on the tire side that
left the ground first. Now tighten the opposite tweak
screw (the one that left the ground last) the same
amount. Recheck the tweak. Continue to make
these adjustments until both tires leave the ground
at the EXACT SAME TIME. Always loosen one
15
screw first, then tighten the opposite screw the
same amount.
MAKE THESE ADJUSTMENTS BEFORE RACING