Pan Car Setup and Troubleshooting
Problems can come up in the midst of competition. Either the car is not handling properly on the track
or there are problems with equipment. Troubleshooting problems should be performed in a methodical
manner. Work patiently and always make a single change at a time and observe the result(s) of that
change. Also take good notes of the changes and the resulting effects. Over time, you will develop
enough experience and knowledge to readily recognise the root cause of a problem and correct it.
Description
of Problem
Possible Cause
of Problem
Corrective Measure
Car is oversteering
Rear tire compound is too hard.
Change to softer rear tire compound.
Front tire compound is too soft.
Change to harder front tire compound.
Front tire diameter is too large.
Reduce the front tire diameter.
Remember to re-adjust the ride height.
Front suspension springs are too soft.
Change to stiffer front springs.
Rear pod movement is too tight.
Loosen the rear pod (T-bar to main
chassis) screws to increase rear pod
travel without excessive side to side
movement. For even better rear pod
movement and control, you can switch
to an optional ball mount suspension
set.
Grease on the rear friction damper
plates is too thick.
Apply thinner grease on the rear friction
damper plates to increase movement of
the rear pod. For even smoother
response, you can switch to Teflon
friction damper plates.
Spring tension on the coil damper or
rear shock absorber is too high.
Decrease the spring tension by
removing spacers or switch to a softer
spring to transfer the driving load to the
rear end. Also, lightly grease the coil
damper shaft for smoother movement.
Spring tension on the friction damper
plates is too high.
Switch to softer springs to decrease the
amount of compression applied to the
friction damper plates. For smoother
response and easier adjustments,
switch to using an adjustable friction
damper post assembly.
Viscosity of oil in rear shock absorber is
too high.
Change to a lower viscosity oil in rear
shock absorber.
Ball differential setting is too tight.
Re-adjust the ball differential to the
proper setting.
Ball differential setting is too loose.
Adjust the rear right axle nut to tighten
the ball differential setting and decrease
slippage on acceleration.
Ball differential is damaged.
Replace damaged ball differential parts.
Thrust bearing in the ball differential is
not slipping properly.
Replace thrust bearing assembly with a
properly oiled one piece thrust bearing
for smoother cornering response.
Car is
understeering
Rear center of gravity is too high.
Lower the rear end center of gravity
using an adjustable ride height gear
case to raise the rear axle ride height.
Rear wing down force is too low.
Change to a rear wing with three wings
(instead of two for increased wing
surface area) and/or a higher wing
angle. For improved rear wing down
force, a rear diffuser set will improve
the airflow over the rear wing for higher
down force.
Front wing down force is too high.
Change to a smaller front wing with a
lower angle.
Toe-out angle of front tires is too large.
Toe-in front wheels and increase toe-in
angle as needed.
Front tires experience "edge bite" on
hard cornering.
Round the shoulder of the front tires.
Steering servo is too fast in response.
Trim steering response if possible.
Front tire compound is too hard.
Change to softer front tire compound.
Front tire diameter is too small.
Change the front tires to a larger
diameter tire set or reduce the diameter
of the rear tires.
Rear tire compound is too soft.
Change to harder rear tire compound.
Front suspension springs are too stiff.
Change to softer front springs.
Chassis flexes too much.
Increase chassis stiffness by changing
from the stock chassis plate to a hard
carbon-type chassis plate or add the
optional FRP upper chassis set (Tamiya
Part No. 53186).
Rear pod movement is too loose.
Tighten the rear pod (T-bar to main
chassis) screws to limit rear pod travel.
Grease on the rear friction damper
plates is too thin.
Apply thicker grease on the rear friction
damper plates to slow movement of the
rear pod.
Spring tension on the coil spring
damper or rear shock absorber is too
low.
Increase the spring tension with
additional spacers to transfer the
driving load to the front end.
Viscosity of oil in rear shock absorber is
too low.
Change to a higher viscosity oil in rear
shock absorber.
Ball differential setting is too tight.
Adjust the rear right axle nut to loosen
the ball differential setting and slightly
increase slippage on acceleration.
Front end ride height is higher than rear Increase rear end ride height using an
end ride height.
adjustable ride height gear case to
increase front end steering.
Weight distribution is lighter at the front Reduce weight of rear end and/or move
end.
weight distribution forward. You can
also switch to a different chassis that
allows repositioning of the batteries for
better weight distribution.
Car does not turn
in either direction
evenly.
Front wing down force is low.
Change to a larger front wing with a
higher angle.
Toe-in angle of front wheels is too
large.
Toe-out front wheels and decrease toein angle as needed. A slight toe-out
may be necessary.
Steering servo is too slow in response.
Change to a faster steering servo.
Chassis is tweaked.
Adjust suspension settings to remove
chassis tweak.
Servo horn neutral position is not set
properly.
Set the servo horn in neutral position
with equal steering arm length.
Steering trim for neutral position of the
radio transmitter is not properly set.
Adjust steering trim with radio
transmitter steering in neutral position.
Steering arm lengths are not equal.
Adjust left or right steering arm length.
Front wheels are not in even alignment. Properly align front right or left wheel:
whichever needs adjustment.
Car steering is
unstable on
straight-aways
Servo is not firmly secured to the
chassis.
Secure the servo to the chassis with
glass tape and servo tape.
Servo saver is worn or loose.
Tighten the servo saver to the servo or
replace servo saver components.
Bent steering arm(s).
Straighten out or replace bent steering
arm(s).
Bent upright.
Replace bent upright.
Differential is not operating smoothly.
Clean and properly lubricate differential
components. Replace any diff balls,
housings, thrust bearings, etc. as
needed.
Uneven tire wear.
Replace and/or true tries to even
diameters on each side, both front and
rear as needed.
Uneven bearing wear.
Replace worn bearings.
Bent rear axle.
Straighten or replace rear axle.
Unbalanced weight distribution on
chassis.
Make tweak adjustment to balance
chassis.
Rear pod was not assembled with
proper alignment.
Reassemble rear pod on a flat surface
for proper alignment.
Chassis is warped.
Replace chassis plate or T-bar as
needed.
Front wheels are not in even alignment. Properly align front right or left wheel:
whichever needs adjustment.
Tires are not glued properly.
Glue the tires securely.
Front tires are in toe-out condition.
Adjust front tires for toe-in condition.
Inadequate toe-in angle.
Increase toe-in angle.
Wheel is not firmly secured with lock
nut.
Tighten the lock nut to hold the wheel
in position.
Servo is not firmly secured to the
Secure the servo to the chassis with
Uneven tire wear
chassis.
glass tape and servo tape.
Servo saver is worn or loose.
Tighten the servo saver to the servo or
replace servo saver components.
Steering trim for neutral position of the
radio transmitter is not properly set.
Adjust steering trim with radio
transmitter steering in neutral position.
Steering blocks are creating
oversensitive steering response.
Change to offset steering blocks.
Uneven tire wear.
Replace and/or true tires to even
diameters on each side, both front and
rear as needed.
Uneven bearing wear.
Replace worn bearings.
Steering arm lengths are not equal.
Adjust left or right steering arm length.
Bent steering arm(s).
Straighten out or replace bent steering
arm(s).
Bent upright.
Replace bent upright.
Too much play in front end
components.
Replace excessively worn components
as needed.
Uneven front spring tension or length.
Either replace the shorter spring or
place a greater preload on it with
spacers.
Differential is not operating smoothly.
Clean and properly lubricate differential
components. Replace any diff balls,
housings, thrust bearings, etc. as
needed.
Bent rear axle.
Straighten or replace rear axle.
Unbalanced weight distribution on
chassis.
Make tweak adjustment to balance
chassis.
Rear pod was not assembled with
proper alignment.
Reassemble rear pod on a flat surface
for proper alignment.
Chassis is warped.
Replace chassis plate or T-bar as
needed.
T-bar mounting screws are loose.
Tighten T-bar mounting screws as
needed.
Countersunk T-bar mounting holes are
damaged.
Replace the T-bar and mounting
screws.
Radio interference is causing the
steering servo to glitch.
Identify and eliminate source of radio
interference (also see "Radio
transmitter is not working."
Unbalanced weight distribution on
chassis.
Make tweak adjustment to balance
chassis.
Uneven front spring tension or length.
Either replace the shorter spring or
place a greater preload on it with
spacers.
Unbalanced wheels.
Balance the wheels using lead tape
used for balancing golf clubs.
Front wheels are not in even alignment. Properly align front right or left wheel:
whichever needs adjustment.
Car ride is very
bumpy
Steering arm lengths are not equal.
Adjust left or right steering arm length.
Bent steering arm(s).
Straighten out or replace bent steering
arm(s).
Bent upright.
Replace bent upright.
Rear axle intermittently seizes.
Clean and lubricate rear axle assembly
and replace bearings as needed.
Differential is not operating smoothly.
Clean and properly lubricate differential
components. Replace any diff balls,
housings, thrust bearings, etc. as
needed.
Bent rear axle.
Straighten or replace rear axle.
Rear pod was not assembled with
proper alignment.
Reassemble rear pod on a flat surface
for proper alignment.
Chassis is warped.
Replace chassis plate or T-bar as
needed.
Unbalanced wheels.
Balance the wheels using lead tape
used for balancing golf clubs.
Wheel is not firmly secured with lock
nut.
Tighten the lock nut to hold the wheel
in position.
Tires are rubbing against other
components.
Increase tire clearance for free
movement.
Both front and rear tire compounds are
too hard.
Change to softer tire compounds for the
front and rear.
Spring on damper unit is too stiff.
Replace damper spring with a softer
spring.
Damper fluid is too viscous.
Replace damper fluid with a lower
viscosity fluid.
Friction damper plate grease is too
viscous.
Replace friction damper plate grease
with a thinner grease.
Too much play in front end
components.
Replace excessively worn components
as needed.
Too much play in rear end components. Replace excessively worn components
as needed.
Worn spur or pinion gear teeth.
Replace worn gear and properly set
gear mesh.
Worn motor armature.
Replace any worn armature components
as needed.