Hudy X-Ray X10 User manual

FOR ALL 1/8
OFF-ROAD
& TRUGGY
®

2
CONTENTS
Introduction 3
Equipment and Tools 4
Set-up System Components 4
Tools and Equipment 5
Assembling and Installing the Set-up Stands 7
Assembling the Set-up Stands 7
Assembling the Set-up Board 8
Installing the Set-up Stands 8
Overview of Car Set-up 9
Downstops 10
Effects of Downstop Adjustment 10
Measuring Downstops 10
Adjusting Downstops 11
Ride Height 12
Effects of Ride Height Adjustment 12
Measuring Ride Height 12
Adjusting Ride Height 13
Camber 14
Effects of Camber Adjustment 14
Measuring Camber 14
Adjusting Camber 16
Track-width 14
Effects of Track-width Adjustment 16
Measuring Track-width 16
Adjusting Track-width 17
Caster 18
Effects of Caster Adjustment 18
Measuring Front Caster 18
Adjusting Front Caster 19
Toe 20
Effects of Toe Adjustment 20
Measuring Toe 20
Adjusting Toe 21
Steering 22
Ackermann 22
Servo Saver Preload 23
Bump Steer 23
Roll Center 24
Front Roll Center 24
Rear Roll Center 25
Shock Absorbers 26
Shock Damping 26
Shock Pistons 26
Shock Oil 27
Shock Springs 27
Shock Mounting Position 28
Shock Preload 28
Kick-up (Front) 29
Effects of Front Kick-up Adjustment 29
Adjusting Front Kick-up 29
Anti-squat (Rear) 30
Effects of Rear Anti-squat Adjustment 30
Adjusting Rear Anti-squat 30
Wheelbase 31
Effects of Wheelbase Adjustment 31
Adjusting Wheelbase 31
Anti-roll Bars 32
Effects of Anti-roll Bar Adjustment 32
Adjusting Anti-roll Bars 32
Rear Wing 33
Effects of Rear Wing Adjustment 33
Adjusting the Rear Wing 33
Clutch 34
Clutch Springs 34
Clutch Shoe Orientation 34
Differentials 35
Differential Oil 35
Differential Gears 36
Optional Differentials (XRAY Active Diff™) 36
Gearing 37
Primary Drive Ratio 37
Gear Mesh Adjustment 37
Wheels, Tires and Inserts 37
Recommended Chemicals for Off-road Cars 39

3
INTRODUCTION
Top-competition off-road cars/truggies are precision racing machines that feature multiple
adjustments that allow you to set up for any track condition. Most modern off-road cars/
truggies include innovative set-up features that allow you to change adjustments quickly
to achieve a full range of adjustment.
The HUDY Off-road Set-up Book describes how to adjust your off-road car/truggy to suit
your driving style. For each individual set-up area, we describe the effects of changing
the adjustment and how to make the adjustment.
When setting up the car/truggy it is very important that the car sits on an ultra-flat surface.
We strongly recommend using high-quality HUDY professional set-up tools – including
an ultra-flat set-up board and marking decal – for every set-up adjustment.
The Basic Set-Up Sheet for your vehicle is always a very good overall starting point. After
rebuilding the chassis, or in case you become lost with your set-up, always return to the
basic starting set-up. If you choose to experiment with set-up, make small adjustments
one at a time, and see if you find any improvement with each adjustment. We strongly
advise you to record and keep track of your set-up changes, record which set-ups work
best at different racetracks under various conditions.
If you own an XRAY model racing car then you can use blank XRAY Set-Up Sheets to
record your data and set-ups or use the unique Virtual Online Database set-up sheets at
www.teamxray.com where you can upload and share your set-up sheets or search for
other set-up sheets posted by factory team drivers or search particular set-up for your
track. The XRAY Virtual Online Database features thousands of set-up sheets and is the
world’s most unique set-up sheet source for your reference.
IMPORTANT!
The adjustment possibilities and methods of adjustment shown in this HUDY Off-road
Set-up Book are particular to the XRAY XB808 1/8 off-road nitro buggy. The general
theory behind the adjustments applies to all off-road vehicles, though the manner in
which the measurements and adjustments are made may differ on other vehicles. Some
of the off-road cars may not have possibility for some adjustments or may require use of
some other optional parts to be able to perform some of the set-up adjustments. Always
refer to the original manufacturer’s documentation for explicit instructions on how to
make set-up adjustments.

4
EQUIPMENT AND TOOLS
When setting up, operating and maintaining your off-road car or truggy, we strongly
recommend using high-quality professional HUDY set-up equipment and tools.
SET-UP SYSTEM COMPONENTS
#108805 Exclusive Alu Set-Up System
For All 1/8 Off-road Cars & Truggies
• CNC-machined alu. and acrylic components
• fully ball-bearing equipped
• precision engraving
• directly measures camber, camber rise,
caster, toe, steering throw symmetry
• easy one-screw assembly/disassembly
#107703 Droop Gauge Support Blocks
• CNC-machined high-grade aluminum
• precision engraving
• supports chassis when checking
downstops
• extra-high 30mm blocks for 1/8 off-road
cars & truggies
• used with 107717 Droop Gauge
#107717 Droop Gauge
• CNC-machined high-grade aluminum
• precision engraving
• measures downstops for off-road
vehicles when used 107703 Droop
Gauge Support Blocks
#108202 Set-Up Board
• exceptionally flat, warp-resistant
surface
• lightweight, easy to carry
• provides perfectly flat reference surface
for chassis set-up
• must be used for any set-up
adjustments
#108212 Set-Up Board Decal
• self-adhesive set-up decal for 108202
Set-Up Board
• accurate, clear markings for adjustment
of 1/8 Off-road cars & truggies
• tough, smooth, liquid-resistant plastic
surface
• used for track width adjustment and
checking
#108860 Alu Nuts for Set-up System
• CNC-machined alu nuts for quick &
easy attachment of set-up system plates
to wheel axles
#108841 Truggy Upside Measure Plate
• CNC-machined upside measure plate
(toe plate) for setting up 1/8 truggies
• made of high-quality, tough acrylic
plastic
• precision engraved markings for instant,
reliable readings
• used for the adjustment of: camber &
camber rise, caster, front and rear toe,
steering throw symmetry
• must be used with the #108805 Set-up
System

5
TOOLS & EQUIPMENT
Turnbuckle Wrenches
• precision turnbuckle wrenches designed
exclusively by HUDY from special self-
developed, world-renown HUDY Spring
Steel™ to ensure maximum strength,
durability, and long life
• additionally hardened to provide
unmatched life span
• wrench head shape is hand-ground on
a precision grinding machine to ensure
a very precise shape to a snug fit on the
turnbuckle
•
the fork end of the tool is additionally
ground flat to keep the tool shape as thin as
possible for very easy access in restricted
areas
• available in 3 sizes: 3mm (#181030),
4mm (#181040), and 5mm (#181050)
HUDY Tools
• Allen 1.5 / 2.0 / 2.5mm
(HUDY #111549 / #112049 / #112549)
• Phillips 5.0mm
(HUDY #165049)
• Socket 5.0 / 5.5mm
(HUDY #170058 / #170059)
#182010 Flywheel Tool
• CNC-machined professional Flywheel
Tool off-road and on-road nitro vehicle
clutches
• flywheel holder holds all modern RC nitro
car flywheels with 2-to-4 pin designs,
allowing you to loosen or tighten the
flywheel nut very comfortably and
easily.
• use with 107581 Wrench-Glowplug /
Clutchnut to hold and loosen/tighten
flywheel nuts quickly & easily
• other features (including clutch gap
measurement, XCA-style clutchbell
holder) for use with on-road XCA-style
clutches
#107570 Wheel Nut Tool
• CNC-machined hardcoated tool for easy
loosening/tightening 17mm wheel nuts
on 1/8 off-road cars and truggies
• oversized handle gives superior torque
• robust design, machined from one piece
• hard anodized for extra-long lifespan
#107581 Wrench-Glowplug / Clutchnut
• unique, highly-useful combination tool
for nitro racing includes the following:
• 10mm socket wrench for Centax type
flywheel nut
• 8mm socket wrench for glowplug
• 5mm hex bit for suspension pivotballs
• extended 8mm glowplug wrench reaches
glowplug even in deep cylinder heads
• made of world-renowned HUDY
Spring Steel™ for highest strength and
durability
• lightweight, perfect-fit tool
• laser-engraved for easy tool
identification

6
#107610 Exhaust Spring/Caster Clip Remover
• designed to easily and quickly remove
caster clips and exhaust springs
• tip from specially hardened steel
• very light non-slip duraluminum handle
• very durable, long life
#107600 Reamer For Lexan Bodies
• professional-quality reamer cuts perfect
holes 0-18mm diameter
• exclusive design by HUDY
• very light non-slip duraluminum handle
• special CAD-designed cutting head, hand-
ground on specially-modified production
machinery
• perfect & comfortable cutting and use
Arm Reamer
• designed specifically for RC use, this
arm reamer precisely resizes plastic
holes without creating excessive slop,
allowing you to build a perfect free-moving
suspension
• comfortable molded handle
• quick & easy to use
• available for different size pins: 3.5mm
pins (#107632), 3.0mm pins (#107633),
4.0mm pins (#107634).
#106000 Drive Pin Replacement Tool
• compact, rugged multi-use tool set for
replacing 3mm drive pins in drive shafts
• heavy-duty construction for long life
• replacement pin sets available separately:
3x14 (#106050)
3x12 (#106051)
3x10 (#106052)
#104140 HUDY Engine Break-In Bench
• the ultimate tool for easy, safe, and
professional break-in of your .12/.15/.21
engine
• suits all bump-start SG crank engines
• allows for a controlled break-in process that
reduces wear & tear on engine components
and increases performance, reliability, and
longevity
• constructed of top-quality components of
tough aluminum and spring steel
• comes partially assembled from the factory

7
ASSEMBLING AND INSTALLING THE SET-UP STANDS
When you are measuring and adjusting track-width, camber & camber rise, caster,
toe, steering throw symmetry, and tweak, you will need to assemble and install the
set-up stands.
When you are measuring downstops and ride height, you do not need to use the set-up
stands.
ASSEMBLING THE SET-UP STANDS
The set-up stands of the Exclusive Alu. Set-Up System For All 1/8 Off-road Cars &
Truggies must be assembled in order for you to use them. These stands were designed
for quick and easy “one screw” assembly and disassembly
The set-up stands consist of the
following pieces:
• alloy side plates front (2)
• alloy side plates rear (2)
• alloy camber gauges (4)
• acrylic toe gauge (1)
➊Attach a camber gauge to a side plate
using a screw through the ball-bearing at
the top of the camber gauge.
➋Using a 2.0mm Allen wrench, tighten
the screw until snug.
➌Make sure the stand operates freely
without binding.

8
➋Remove the paper from the rear of the
decal, exposing the adhesive backing.
➌Center the decal on the board, and
then press the entire decal firmly onto the
board.
➍Rub the decal until it is flat and
completely adhered to the board.
INSTALLING THE SET-UP STANDS
After you have assembled the four set-up stands, mount them to your car as follows.
➊Remove the wheels from the car. In
place of the wheels, mount a set-up stand
on each of the four axles. In front use side
plates with scale, while in rear use side
plates without scale (only with HUDY logo).
➋The camber gauge of each stand
should face outward so it is easy to read.
The camber gauge of the front stand
should face forward, while the camber
gauge of the rear stand should face
rearward.
➌ Place the car (with the mounted set-up
stands) on the set-up board.
FRONT
REAR
ASSEMBLING THE SET-UP BOARD
The completed set-up board consists of the Set-Up Board and the Set-Up Board Decal.
IMPORTANT:
You should always use only the HUDY set-up board when setting up your car with the
HUDY All-In-One Set-Up Solution. This exceptionally flat, warp-free board will ensure
accurate, precise measurements.
➊Clean the board with a soft cloth to
remove any debris or contaminants.

9
OVERVIEW OF CAR SET-UP
When setting up your off-road car/truggy, we recommend setting it up in the order
indicated in the table below. The order of the settings has been determined as the most
logical to set up your car/truggy properly and easily. Also, certain settings must be
made before others, as changing one setting will impact another setting.
The table below also lists the set-up components to be used to measure or adjust a
particular setting.
TO MEASURE OR ADJUST USE
Downstops
• Flat set-up board
• Droop gauge support blocks
• Droop gauge
Ride height • Flat set-up board
• Droop gauge
Camber
• Flat set-up board
• Droop gauge support blocks
• Assembled set-up stands
Track-width • Flat set-up board
• Board decal
Caster • Flat set-up board
• Assembled set-up stands
Toe
• Flat set-up board
• Droop gauge support blocks
• Assembled set-up stands
• Toe gauge
There are several types of suspensions used on RC cars, including pivotball and C-hub
suspensions. Each suspension type has its own way of making adjustments for
downstops, camber, caster, toe, etc. For detailed information on adjusting the settings on
your car, refer to the appropriate set-up manuals for your car.
When setting up your off-road car/truggy, you should always prepare it so it is ready to
run, though without the body. This means you should install all electronics, batteries, and
fill the fuel tank (nitro only).

10
1.1 DOWNSTOPS
Downstops limit how far the suspension arms travel downward, which determines how
far upward the chassis rises. This affects the car’s handling (due to effects on camber
and roll-center) and the ability of the tires to “follow” the track. The effects may change
with the type of track and/or amount of grip available. Downstops are a very sensitive
adjustment, since they alter weight transfer, and all aspects of chassis performance are
affected: braking, acceleration, jumping, traction and rough track handling.
More suspension travel (lower downstop value) makes the car more responsive but less
stable; it is also typically better on a bumpy track or on a track with slow corners. This
allows the chassis to “pitch” rearward or forward more under acceleration or braking
(respectively), which results in more weight transfer.
Less suspension travel (higher downstop value) makes the car more stable and is
typically better on a smooth track. This prevents the chassis from “pitching” rearward
or forward too much under acceleration or braking (respectively), which results in less
weight transfer.
It is very important to have the same downstop settings on the left and right sides
of the car.
EFFECTS OF DOWNSTOP ADJUSTMENT
FRONT DOWNSTOPS
Higher downstop value
(arm is higher, less
travel)
• Decreases front chassis upward travel on-throttle
• Less rearward weight transfer
• Better on smooth tracks
• More on-power steering
• More responsive in direction change
Lower downstop value
(arm is lower, more
travel)
• Increases upward chassis travel on-throttle
• More rearward weight transfer
• Increases rear traction on corner exit
• Better on bumpy tracks
REAR DOWNSTOPS
Higher downstop value
(arm is higher, less
travel)
• Decreases rear chassis upward travel off-throttle or
under braking
• Less forward weight transfer
• Better on smooth tracks
Lower downstop value
(arm is lower, more
travel)
• Increases rear chassis upward travel off-throttle or
under braking
• Less stable under braking
• Increases steering on corner entry
• Better on bumpy tracks
• More turn-in
MEASURING DOWNSTOPS
INITIAL STEPS SET-UP COMPONENTS
Prepare the car as follows Use the following set-up components
• Shocks: Attach the shocks
• Anti-roll bars: Attach the anti-roll bars
• Wheels: Remove the wheels
• Droop Gauge Support Blocks #107703
• Droop Gauge #107717
• Set-up Board #108202

11
➊Place the droop blocks on the flat set-
up board, and then place the flat part of
the chassis (not the angled part) on the
blocks. Make sure the chassis is solidly
mounted on the support blocks so it does
not move.
➋Lift and drop the suspension arms so
that they settle in their lowest positions.
➌Using the droop gauge, measure the
downstop values at the front and rear of
the car.
FRONT DOWNSTOPS:
Measure the front downstop values under
the round part of the front wheel axles. DO
NOT measure under the hex part.
The values shown on the droop gauge
indicate how many millimeters the
suspension drops below the level of the
chassis.
REAR DOWNSTOPS:
Measure the rear downstop values under
the round part of the rear wheel axles. DO
NOT measure under the hex part.
The values shown on the droop gauge
indicate how many millimeters the
suspension drops below the level of the
chassis.
ADJUSTING DOWNSTOPS
FRONT DOWNSTOPS
Increase
Turn IN (or OUT) the front downstop screw
(depending on the car design) so the front
lower arm raises up slightly.
Decrease
Turn OUT (or IN) the front downstop screw
(depending on the car design) so the front
lower arm drops slightly.
REAR DOWNSTOPS
Increase
Turn IN (or OUT) the rear downstop screw
(depending on the car design) so the rear
lower arm raises up slightly.
Decrease
Turn OUT (or IN) the rear downstop screw
(depending on the car design) so the rear
lower arm drops slightly.
IMPORTANT!
Make equal adjustments on both left and right sides of the car.

12
1.2 RIDE HEIGHT
front ride height rear ride height
Ride height is the height of the chassis in relation to the surface it is sitting on, with the car
ready to run. Ride height affects the car’s traction since it alters the car’s center of gravity
and roll center. Differences in ride height alter the car’s attitude (angle of the chassis)
which in an off-road vehicle can effect how it jumps and lands. Because of changes in
suspension geometry and ground clearance, there are negative consequences to altering
ride height too much.
Ride height is measured with the wheels on the car, and the car ready-to-run. Use the
shock preload collars or clips to raise and lower the ride height.
EFFECTS OF RIDE HEIGHT ADJUSTMENT
Decreasing ride height • Increases overall stability
• Better on smooth tracks
Increasing ride height • Decreases overall stability
• Better on bumpy tracks (prevents bottoming)
Front higher than rear
• Increases weight transfer to the rear on-power
• Increases stability
• Decreases steering
Front lower than rear
• Increases weight transfer to front off-power
• Increases steering
• Decreases rear traction
• May cause car to nosedive off jumps
MEASURING RIDE HEIGHT
INITIAL STEPS SET-UP COMPONENTS
Prepare the car as follows Use the following set-up components
• Shocks: Attach all shocks
• Anti-roll bars: Attach all anti-roll bars
• Wheels: Attach all wheels. Both left and
right wheels at the front or rear should be
the same diameter
• Flat Set-up Board #108202
• Droop Gauge #107717
➊Place the car on the set-up board.
➋Lift the front of the car and let it fall back
to the set-up board by itself.
➌Using the droop gauge, measure the
ride height value at the front of the car.

13
➍Lift the rear of the car and let it fall back
to the set-up board by itself.
➎Using the droop gauge, measure the
ride height value at the rear of the car.
FRONT RIDE HEIGHT
Place the droop gauge under the front of the chassis (under the FLAT part of the chassis,
not the angled part) and measure the difference between the set-up board and the bottom
of the chassis.
The 0mark on the droop gauge is equal to 30mm ride height. A negative value on the
droop gauge is lower than the 30mm reference height. For example, if the chassis is at
-3mm on the droop gauge, your ride height is 30-3mm = 27mm.
REAR RIDE HEIGHT
Place the droop gauge under the rear of the chassis (under the FLAT part of the chassis)
and measure the difference between the set-up board and the bottom of the chassis.
The 0mark on the droop gauge is equal to 30mm ride height. A negative value on the
droop gauge is lower than the 30mm reference height. For example, if the chassis is at
-3mm on the droop gauge, your ride height is 30-3mm = 27mm.
ADJUSTING RIDE HEIGHT
Adjust ride height using spring preload only; DO NOT adjust ride height using downstop
screws.
Your car may use threaded spring preload collars or preload spacers.
Preload setting Threaded preload collar Preload spacers
Increase TIGHTEN collar so it moves DOWN
the shock body
Use THICKER spacers
above the spring
Decrease LOOSEN collar so it moves UP the
shock body
Use THINNER spacers
above spring
FRONT RIDE HEIGHT
Increase
INCREASE preload on both FRONT springs
EQUALLY.
Decrease
DECREASE preload on both FRONT
springs EQUALLY.
REAR RIDE HEIGHT
Increase
INCREASE preload on both REAR springs
EQUALLY.
Decrease
DECREASE preload on both REAR springs
EQUALLY.

14
1.3 CAMBER
-
+
r
c
a
m
b
e
Camber is the angle of a wheel to the surface on which the car is resting (with wheels and
shock absorbers mounted).
• Zero degrees (0°) of camber means that the wheel is perpendicular to the reference
surface.
• Negative camber means that the top of the wheel is leaning inwards towards the
centerline of the car.
• Positive camber means that the top of the wheel is leaning outwards from the centerline
of the car.
Camber affects the car’s side traction. Generally more negative (inward) camber means
increased grip since the side-traction of the wheel increases. Adjust front camber so that
the front tires wear flat. Adjust rear camber so that the rear tires wear slightly conical to
the inside.
The amount of front camber required to maintain the maximum contact patch also depends
on the amount of caster. Higher caster angles (more inclined) require less negative camber,
while lower caster angles (more upright) require more negative camber.
EFFECTS OF CAMBER ADJUSTMENT
FRONT CAMBER
More negative (more inclined) • More steering
Less negative (less inclined) • Less steering
REAR CAMBER
More negative (more inclined) • Decreases rear traction entering and in corners
Less negative (less inclined)
• Increases rear traction entering and in corners up
to a point
• If the shock is too vertical and traction is lost, the
traction will be lost very abruptly and the car will
be hard to control
MEASURING CAMBER
INITIAL STEPS SET-UP COMPONENTS
Prepare the car as follows Use the following set-up components
•Shocks: Attach all shocks
•Anti-roll bars: Detach all anti-roll bars
•Wheels: Remove all wheels
• Flat Set-up Board #108202
• Assembled Set-up Stands #108805
• Droop Gauge Support Blocks #107703
➊Assemble the set-up stands.
➋Mount the set-up stands on the axles.
➌Place the droop blocks on the flat set-up
board, and then place the flat part of the
car chassis (not the angled part) on the
blocks.

15
➍Push on the car so the chassis rests flat
atop both droop blocks at front and rear.
➎Read the camber setting from the
camber gauge of each of the four set-up
stands.
Each graduated mark indicates a 1° camber
value. You should be able to set camber
with a resolution of 0.5°.
ADJUSTING CAMBER
FRONT CAMBER
Increase (more –ve)
SHORTEN the front upper camber link.
Decrease (less –ve)
LENGTHEN the front upper camber link.
FRONT CAMBER
Increase (more –ve)
SHORTEN the rear upper camber link.
Decrease (less –ve)
LENGTHEN the rear upper camber link
NOTE:
Changing the front camber will affect front toe. After setting the camber you must re-
adjust the toe and then re-check the camber settings again. It may take a few repetitions
of these steps to ensure that both camber and toe are set to the desired values.
REAR CAMBER

16
1.4 TRACK-WIDTH
Track-width is the distance between the outside edges of the wheels, front or rear, and it
affects the car’s handling and steering response. It is important that front or rear track-
width is adjusted symmetrically, meaning that the left and right wheels (at one end of the
car) must be the same distance from the centerline of the chassis.
EFFECTS OF TRACK-WIDTH ADJUSTMENT
FRONT TRACK-WIDTH
Wider
• Decreases
front grip
• Increases understeer
• Slower steering response
• Use to avoid traction rolling
Narrower
• Increases front grip
• Decreases understeer
• Faster steering response
REAR TRACK-WIDTH
Wider
• Increases rear grip at corner entry
• Increases high-speed on-throttle steering
• Use to avoid traction rolling
Narrower • Increases grip at corner exit
• Increases high-speed understeer
MEASURING TRACK-WIDTH
INITIAL STEPS SET-UP COMPONENTS
Prepare the car as follows Use the following set-up components
• Shocks: Attach all shocks
• Wheels: Attach all wheels. Both left and
right wheels at the front or rear should
have the same offset
• Flat Set-up Board #108202
• Board Decal #108212
➊Place the car on the set-up board.
➋Align the center of the car with the
centerline on the set-up board decal. Make
sure both front and rear are centered on the
decal.
front track-width rear track-width

17
➌Make sure the front wheels rest on
the front track-width graduation marks.
The amount of toe-in/toe-out has direct
influence on the track width so make sure
to measure at the part where the car is
widest.
➍Make sure the rear wheels rest on the
rear track-width graduation marks.
FRONT TRACK-WIDTH
Look where the outer edge of each front wheels lie on the front track-width graduation
marks. Use a straight-edge against the wheel if necessary to see what the measurement
is.
The measurement represents the distance from the car’s centerline to the outer edge of
each wheel.
For example, on a 308mm wide buggy car, the measurement should be close to
154mm (½ the track-width) for each wheel.
REAR TRACK-WIDTH
Look where the outer edge of each rear wheels lie on the front track-width graduation
marks. Use a straight-edge against the wheel if necessary to see what the measurement
is.
The measurement represents the distance from the car’s centerline to the outer edge of
each wheel.
For example, on a 306mm wide buggy car, the measurement should be close to
153mm (½ the track-width) for each wheel.
ADJUSTING TRACK-WIDTH
Different cars may use different methods for track-width adjustment.
C-HUB SUSPENSION
Normally you cannot adjust the track-
width of a car with C-hub suspension due
to the design of the suspension system.
The suspension arms and other parts are
designed to give you the correct track-
width automatically. Optional off-set wheel
axles may be offered to adjust track-
width.
PIVOTBALL SUSPENSION
Cars with adjustable pivotball-style suspension can change track-width by adjusting the
pivotballs into or out of the suspension arms.
IMPORTANT!
Make equal adjustments on both left and right sides of the car.

18
1.6 CASTER
c
a
s
t
e
r
Caster describes the angle of the front steering block with respect to a line perpendicular
to the ground. The primary purpose of having caster is to have a self-centering steering
system. Caster angle affects on- and off-power steering, as it tilts the chassis more or
less depending on how much caster is applied.
For the purpose of RC cars, it is generally recommended that you use a steeper caster
angle (more vertical) on slippery, inconsistent and rough surfaces, and use a shallower
caster angle (more inclined) on smooth, high-grip surfaces.
CAMBER vs. CASTER
Camber is all about contact patch – keeping as much tire on the ground as possible.
Camber and caster are related in that caster can afford an amount of EFFECTIVE CAMBER
change when the front wheels are turned in a corner.
Caster has the effect of progressively leaning the front tires into the direction of the
corner. The more the caster angle is laid-back, the greater the effective camber change
when the wheels are turned. This happens because the tops of the wheels BOTH TILT
towards the inside of the corner; the wheels “dig in” more, counteracting the centrifugal
forces pushing the car to the outside.
Compare that to the static camber of the wheels, which is adjusted with the car sitting
on a level surface and the wheels pointed straight ahead. Static camber adjustments
primarily affect the outside wheels, since these are the wheels that bear the majority of
the load during cornering.
Hence, the amount of front camber required to maintain maximum tire contact largely
depends on the amount of caster. A steeper caster angle requires more camber, while a
shallower caster angle requires less camber.
TOTAL CASTER ANGLE
Total caster angle also depends on the front kick-up angle.
To determine the total caster angle, combine the kick-up angle + C-hub caster angle.
Example: 10° front kick-up + 10° caster in C-hub = 20° total caster
EFFECTS OF CASTER ADJUSTMENT
Less caster angle
(more vertical)
• Decreases straight-line stability
• Increases off-power steering at corner entry
• Increases suspension efficiency
More caster angle
(more inclined)
• Increases straight-line stability
• Decreases off-power steering at corner entry
• Makes the car more stable through bumpy track conditions
MEASURING FRONT CASTER
INITIAL STEPS SET-UP COMPONENTS
Prepare the car as follows Use the following set-up components
• Shocks: Attach all shocks
• Wheels: Remove all wheels
• Flat Set-up Board #108202
• Assembled Set-up Stands #108805

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➊Assemble the set-up stands.
➋Mount the set-up stands on the axles.
➌Place the car on the set-up board.
➍Read the caster angle from the side of
the front set-up stands.
Read the caster angle on the side plates
between the imaginary line that goes from
the top pivot point to the bottom pivot
point. Each graduated mark indicates a 2°
camber value. You should be able to set
camber with a resolution of 1°.
ADJUSTING FRONT CASTER
There are several different ways to adjust
caster on a car with C-hub suspension,
depending on the design of the car:
• Non-adjustable C-hubs (for example,
XB808): change to C-hubs of different
caster values
• Adjustable C-hubs (for example,
XB8EC): change the C-hub eccentric
pin holder.
IMPORTANT!
Make equal adjustments on both left and right sides of the car.

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1.6 TOE
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Toe is the angle of the wheels when looked at from above the car. Toe is used to stabilize
the car at the expense of traction, as it introduces friction and therefore some slip in the
tires.
• When the wheels are parallel with the centerline of the car, toe is 0° (neutral).
• When the wheels are closed towards the front, this is called toe-in (positive value).
• When the wheels are open towards the front, this is called toe-out (negative value).
Front wheels can have either toe-in or toe-out.
Rear wheels should always have toe-in; they should never have toe-out.
Toe may be adjustable at either end of a suspension arm:
• Inboard toe (if available) is typically adjusted by altering the angle of the suspension
arm’s inner pivot pin. Inboard toe adjustment is not available on all vehicles.
• Outboard toe (if available) may be adjusted in two ways: at the front by adjusting the
lengths of the steering rods; at the rear by altering the angle of the suspension arms
inner mounting pin (or other method)
EFFECTS OF TOE ADJUSTMENT
FRONT TOE
Increasing (more toe-in) • Makes car easier to drive
Decreasing
(less toe-in, or more
toe-out)
• Decreases understeer
• Increases steering at corner entry
• Faster steering response
• Less stable under acceleration
• Makes car more difficult to drive
REAR TOE
Increasing (more toe-in)
• Increases understeer
• More stable exiting on-power at corner exit and braking
• Less chance of losing rear traction
• Decreases top speed
Decreasing (less toe-in)
• Less stable at on-power corner exit and braking
• More chance of losing rear traction
• Increases top speed
MEASURING TOE
INITIAL STEPS SET-UP COMPONENTS:
Prepare the car as follows: Use the following set-up components:
• Shocks: Attach all shocks
• Wheels: Remove all wheels
• Flat Set-up Board #108202
• Assembled Set-up Stands #108805
• Toe Gauge (for Truggy #108841)
• Droop Gauge Support Blocks #107703
When using the acrylic toe gauge, the toe gauge does not fit over the pins on the set-up
stands so that the toe gauge is in one position. The toe gauge is designed to slide over
the pins from one side to the other, depending on which wheel you are measuring (left or
right). Follow the instructions carefully.