Traxxas 4104, 4110 User Manual

OPERATING INSTRUCTIONS

COVERS MODEL 4104 AND 4110

FOLLOW ALL THE INSTRUCTIONS IN THIS AND THE

WARNING!

ACCOMPANYING MANUALS IN ORDER TO AVOID SERIOUS
DAMAGE TO YOUR MODEL. IF THESE INSTRUCTIONS ARE
NOT FOLLOWED, THE RESULTING DAMAGE WILL BE CON­SIDERED ABUSE AND/OR NEGLECT, THEREBY RELEASING
BOTH TRAXXAS AND YOUR DEALER FROM ANY FURTHER
WARRANTY RESPONSIBILITY.

INTRODUCTION

Thank you for purchasing the Tr axxas Nitro Stampede. This
manual contains the instructions you will need to operate, and
maintain your Nitro Stampede. Look over the manual and
examine the Nitro Stampede carefully before running it. If for
some reason you think the Nitro Stampede is not what you
wanted, then do not continue any further. Your hobby dealer

absolutely cannot accept a Nitro Stampede for return or
exchange after it has been run.

Please read ALL of the Operating Instructions and Precautions

before attempting to drive the Nitro stampede. Even if you are an
experienced R/C enthusiast, continue reading to learn about Nitro
Stampede’s unique features. Pay special attention to the mechani­cal and safety precautions outlined in the manual.

If you have any questions about your new model, feel free to
call Traxxas’ technical support line toll-free at 1-888-TRAXXAS
(1-888-872-9927) Outside the U.S. call 972-613-3300. Technical
support is available Monday through Friday, from 8:30 AM to 5:30
PM Central Time. Technical assistance is also available through
our website at www.traxxas.com (E-mail us at
[e-mail]). We hope that you will enjoy many hours of
fun with your new Nitro Stampede.

FUEL

CAUTION:

ALWAYS FOLLOW THE PRECAUTIONS PRINTED ON

THE CONTAINER OF FUEL. KEEP IT AWAY FROM

FLAMES AND CHILDREN. THE MIXTURE IS FLAMMABLE

AND POISONOUS.

Fuel is the most critical component for making your engine
perform properly. Improper fuels will cause hard starting, poor
performance, and excessive wear on the engine. For the best
performance from your TRX Pro .15 engine, use Traxxas Top
Fuel™. Tr axxas Top Fuel™ is the only model engine racing fuel

which exceeds all of the Traxxas engine warranty requirements,
is specially formulated to resist heat, and is guaranteed to pro­vide the best performance and longest life from your Traxxas
engine. Traxxas cannot guarantee the quality and
consistency of other manufacturers’ fuels. If
Tr axxas Top Fuel™ is not available from your
hobby dealer, the fuels listed below have
been tested by Traxxas and determined to be
satisfactory for use in the
TRX Pro .15.

Dynamite Blue Thunder
Power Master Formula 16
Byron’s Originals Race 1000/2000
Morgan’s Omega (Omega fuel is an airplane

fuel which may be used. The higher oil
content however, will not deliver the same
performance and tuning ease as a good,
special-purpose car fuel)

Some fuels are capable of destroying

your TRX Pro .15 engine! If you must use a

fuel other than those listed, contact TRAXXAS
first, at 1-888-TRAXXAS, to find out if the fuel is safe for use with
TRX engines.

FUEL BOTTLE

CAUTION:

ALWAYS FOLLOW THE PRECAUTIONS PRINTED ON THE

CONTAINER OF FUEL. KEEP IT AWAY FROM FLAMES AND

CHILDREN. THE MIXTURE IS FLAMMABLE AND POISONOUS.

Fuel is usually purchased by the gallon or
quart, so a smaller bottle with a dispensing
tube is required to fill the fuel tank. The fuel
tank in the Nitro Stampede has a capacity of
75cc. The fuel bottle should always be capped
to prevent the fuel from evaporating and becom­ing contaminated with debris or moisture. The
alcohol and nitro contents of the fuel will evapo­rate, thus upsetting the fuel balance and spoiling
the fuel. Do not use old or dirty fuel!

Tr axxas #5001-Fuel Bottle

PERSONAL SAFETY PRECAUTIONS

Every precaution outlined in this manual needs to be followed
to help ensure safe operation. Operate your model sensibly and
with care and it will be exciting, safe, and fun for you and your
spectators. Failure to operate your model in a safe and responsi­ble manner could result in property damage and serious injury.
You alone must see to it that the instructions are followed and
the precautions are adhered to.

The Nitro Stampede is not intended for use by children
without the supervision of a responsible adult. Traxxas

Corporation shall not be liable for any loss or damages, whether
direct, indirect, special, incidental, or consequential, arising
from the use, misuse, or abuse of this product and any chem­ical or accessory required to operate this product.

• The fuel is dangerous and poisonous. Follow all of the direc-

tions and precautions on the fuel container.

• The fuel can look like a cool drink to a young child. Keep it out

of children’s reach.

• The fuel is flammable. Do not allow sparks, flame, or smoking
in the presence of model fuel.

2

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• The engine emits poisonous carbon monoxide gas. Always run
the model in a well-ventilated area. Never attempt to run the
engine indoors.

• The engine and exhaust become extremely hot during use.
Be careful not to touch these parts, especially when refueling.

• Do not drive the Nitro Stampede at night.

•Never, under any circumstances, operate the Nitro Stampede
in crowds of people. The Nitro Stampede is very fast and
could cause injury if allowed to collide with anyone.

• Because the model is controlled by radio, it is subject
to radio interference from many sources that are beyond your
control. Since radio interference can cause momentary losses

of radio control, always allow a safety margin in all directions

around the model in order to prevent collisions.

• The engine can be very loud. If the noise makes you
uncomfortable, wear ear protection. Be considerate of your
neighbors by not running your model early in the morning or
late in the evening.

• Most importantly, use good, common sense at all times.

7.2v BATTERY PACK AND CHARGER

The EZ-Start™ electric starter requires a

7.2 volt rechargeable nicad battery pack.
The battery pack straps to the bottom
of the EZ-Start™ control box with
the supplied tie wraps. The battery
pack must be fully charged in order
to start the engine. It can be
recharged with an overnight “wall
charger”, a peak-detecting charger, or
a 15-minute quick charger. All are available from a hobby dealer.

OTHER REQUIRED EQUIPMENT

To operate the Nitro Stampede, you will need these additional items.

All of these items should be available from your hobby shop.

1. “AA” size batteries for your transmitter(8) and receiver(4)

2. Small phillips head and flat screwdrivers (for adjustments)

3. After-run oil (to protect the engine from corrosion)

4. Spare glow plugs (standard plug, Traxxas part #3230; or
heavy-duty plug, Traxxas part #3231).

5. In-line fuel filter (recommended)

6. Spare fuel line (recommended)

THE TQ RADIO SYSTEM

The Nitro Stampede Model 4110 is equipped with the 2-channel
TQ radio system. The following radio system terms will be
used throughout the rest of these operating instructions.

TWO-CHANNEL RADIO SYSTEM - The radio system in your

model consists of the RECEIVER, the TRANSMITTER, and the
SERVOS. It has two channels, one to operate the throttle, and one
to operate the steering.

Antenna

Throttle Trim

Steering Trim

Throttle Neutral Adjust

Steering Wheel

CHANNEL - The 27 MHZ FREQUENCY BAND is divided into 6
CHANNELS, so that up to six cars can be operated simultaneously.
These CHANNELS are referred to by their number and flag color.
The chart below lists the channels and their flag colors.

27MHZ FLAG COLOR CH# TRAXXAS PART#

26.995 BROWN 1 2031

27.045 RED 2 2032

27.095 ORANGE 3 2033

27.145 YELLOW 4 2034

27.195 GREEN 5 2035

27.255 BLUE 6 2036

CRYSTAL (X-TAL) - The CRYSTAL is the plug-in device that
determines which channel the RADIO SYSTEM will operate on.
For each CHANNEL, there are two CRYSTALS, one for the
RECEIVER and one for the TRANSMITTER. Of those two
CRYSTALS, the one marked with the lower number (.455 MHZ
lower) must be inserted in the RECEIVER.

CLEARING YOUR FREQUENCY - CLEARING your frequency
means checking to be sure no one else in the area is operating
on the same CHANNEL. You should always do this before operating
your model.

NICAD (Ni-Cd) - These terms stand for rechargeable, nickel
cadmium batteries. These batteries are most economical and
can be recharged up to 500 times.

NEUTRAL POSITION - The NEUTRAL POSITION is the standing
position that the SERVOS seek when the TRANSMITTER controls
are at neutral.

TRIM - TRIM is the fine-tuning adjustment of the NEUTRAL
POSITION of the SERVOS. This adjustment is made by turning the
throttle and steering trim knobs on the face of the TRANSMITTER

RED
POSITIVE

BLACK
NEGATIVE

ON/OFF

ANTENNA

SWITCH

4-CELL

BATTERY HOLDER

PART# 3170

Throttle Trigger

Power Switch

Battery
Compartment

Servo Reversing Switches

Power Indicator

Steering (R), Throttle (L)

CH.1 CH.2

TRANSMITTER - The TRANSMITTER is the hand-held radio unit
which sends throttle and steering instructions to the model.

RECEIVER - The RECEIVER is the radio unit inside the model
which receives signals from the TRANSMITTER and relays them

WIRE COLORS

INSTALLING TRANSMITTER BATTERIES

Install 8 “AA” batteries into the bottom of the
transmitter as shown in the drawing.

BLACK
RED
WHITE

RECEIVER

CHANNEL-1

CHANNEL-2

BATTERY

CHANNEL 1

STEERING

SERVO

CHANNEL-2

THROTTLE

SERVO

to the SERVOS.

SERVO - The SERVOS are the small motor units in the model
which operate the steering, and throttle mechanisms.

FREQUENCY BAND - The FREQUENCY band is the radio
frequency that the transmitter uses to send signals to the model.
All Traxxas RTR models operate on a 27 MHZ FREQUENCY BAND.

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

3

4

INSTALLING RECEIVER BATTERIES

The receiver battery holder is located underneath the bat­tery cover. Remove the battery cover by removing the two
body clips from the posts on both sides of the battery holder.

Install 4 “AA” batteries into the battery holder. Alkaline batteries
should be used. Place the battery holder into the battery cover
with the cushioning foam. Secure the battery cover to the chassis
using the two body clips as shown.

ANTENNA SETUP

Locate the plastic tube and the antenna tip (supplied in the bag with
your instructions). Insert the black antenna wire, extending from the
receiver housing, into one end of the tube and push it all the way
through. Spray the wire with glass cleaner to make it easier to insert.

Insert the tube into the antenna mount in the side of the chassis.
Fold the remaining antenna wire over the top of the antenna tube
and secure it with the vinyl antenna tip.

Under no circumstances should you ever cut your antenna wire.
Its length is specially tuned to the frequency band, and cutting it
could severely shorten the radio’s range. On the transmitter, fully
extend the chrome telescopic antenna.

RADIO SYSTEM OPERATION

Your radio system was pre-adjusted before it left the factory, however,
the adjustment should be checked prior to running the truck.

1) Before you ever turn your radio system on, you must “clear”
your frequency. There are six different channels numbered 1
through 6. Each of the six channels is represented by a color.
Look at the crystal in the back of the transmitter to determine
which of the channels your truck is operating on. Clearing your
frequency means checking to be sure that no one else in the
area is operating on the same channel.

2) TIP: Always turn the transmitter on first and off last. This
will prevent the model from receiving stray signals and run­ning out of control. Slide the transmitter switch to the “on”

position. A steady red light
should illuminate. A flashing

red light indicates weak bat­teries. Weak batteries will limit

the range of the radio signal
between your transmitter and
receiver. Loss of the radio signal
can cause you to lose control of
the truck.

3) Tu rn the truck on.The switch is located on the chassis. The ser­vos should jump and move to their idle (neutral) positions.

RADIO SYSTEM ADJUSTMENTS

• THROTTLE NEUTRAL ADJUST

The throttle neutral adjustment is located on the transmitter
face and controls the forward and reverse travel of the throttle
trigger. There are two settings, 50/50 which allows equal travel
for both forward and brake, and 70/30 which allows more travel
for throttle and less for brake. Change the adjustment by press­ing the button and sliding it to the desired position. 70/30 is the
recommended setting while running the Nitro Stampede.

• SERVO REVERSING SWITCHES

On the front of the transmitter there are two switches. One
for throttle and one for steering. Moving the switches reverses
the direction of the corresponding servos. For example, if you
turn your steering wheel right and the model moves left, then
switch the steering servo reversing switch to correct the servo
direction. You may need to adjust the corresponding trim control
after moving the servo-reversing switch.

TOTAL TRIGGER

MOVEMENT

50%

REVERSE

50%

FORWARD

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

NEVER TURN THE TRANSMITTER OR RECEIVER OFF
WHILE THE ENGINE IS RUNNING. THE MODEL COULD
RUN OUT OF CONTROL. (The on/off switch only turns
the receiver on and off. It does not turn off the engine.)

4) With the front wheels off the ground, operate the steering control
on the transmitter (channel 1). Check for rapid operation of the
steering servo and that the steering mechanism is not loose or
binding. If the servo operates slowly, check for weak batteries.
Tu rn the “steering trim” control on the transmitter to adjust the
servo so that the front wheels are pointing straight ahead. Check
to be sure that the wheels do not turn more in one direction than
in the other.

FRONT

STARTING THE ENGINE

STEP 1: INSTALL THE AIR FILTER

Remove the protective cap from the carburetor air intake. Install
the rubber air filter base and pre-lubed foam element onto the car­buretor intake. The foam air filter element may be cleaned and
reused. Always be sure the filter element is oiled properly
before running the engine. For the best
filtration, use the type of oil made for foam
air filters. It should be available locally from
motorcycle shops and small engine repair
shops. Lightweight motor oil or after-run
oil may also be substituted. When the ele­ment gets dirty, clean it with dish soap and
rinse. Next, saturate it with oil and then
squeeze out the excess oil. For extremely
dusty conditions, special two or three­stage, pre-lubed filters are available from
Tr axxas (Part #4062 and #4063).

STEP 2: FILL THE FUEL TANK

0˚ TOE-IN

Wheels pointing straight ahead

5) Operate the throttle trigger on the transmitter to ensure that
the throttle servo is operating properly. When the servo is in
the neutral position, the carburetor should be in its idle position
(you will adjust the engine idle speed later). When the throttle
trigger is pulled all of the way, the carburetor should be in the
fully open position. When the throttle lever is pushed forward,
the brake should be locked and the throttle should not close
any further than when at idle.

RANGE TEST THE RADIO

There are many things such as buildings, power lines, radio
transmitters, etc. which can adversely affect the performance of
your radio system. To make sure you do not have a “runaway”
model, range test the radio system. With the radio system on and
working, hold the truck and have a friend carry the transmitter
away from you the distance you plan to run the truck. Have the
friend operate the controls on the transmitter to be sure that
everything is working at full range.

PREPARING TO RUN

• INSTALLING THE EZ-START BATTERY

Use tie wraps to secure a

fully-charged 7.2 volt
battery back to the EZ­Start control box. Plug
the battery connector
into the face of the
control box. The plug
will only go in one way.

Use a small fuel bottle or bulb to put fuel into the tank. Only fill
the tank to the bottom of the fill neck.The Nitro Stampede can be
carefully refueled while the engine is running.

STEP 3: HIGH-SPEED MIXTURE SETTING

AIR

FILTER

HIGH SPEED
NEEDLE

Note: Your carburetor has been factory preset

for break-in. Do not read just your carburetor

settings unless you suspect a problem.

The following steps are for reference only.

The high-speed mixture screw controls how much fuel enters

the engine during mid and high-speed operation. Turn the high­speed mixture screw clockwise, by hand, until it stops (Do not
tighten or the needle may be damaged). Now, turn the mixture
screw counter-clockwise 2

1

/2complete turns.

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

5

STEP 4: SETTING THE IDLE SPEED

STEP 8: START THE ENGINE

The idle screw regulates the throttle opening to control the idle
speed. The throttle opening at idle should be set as shown in the
drawing. The opening should be 1 to 11/2millimeters at the widest
point in the opening. Note: the engine may not idle well until it is
warmed.

STEP 5: LOW SPEED MIXTURE SETTING

This screw meters the fuel at low speeds. The low-speed mixture
screw is located in the end of the carburetor, inside the throttle
arm. This screw controls how much fuel enters the engine at idle
and low throttle. This adjustment will smooth the idle and improve
acceleration to mid-speed. Make this adjustment with the throttle
closed, after setting the idle. To get the low speed mixture into the
correct range of adjustment, turn it in or out until the head of the
screw is flush (even) with the end of the throttle arm assembly. This
will be the starting point for future adjustments. Fine tuning the
low speed mixture is described on page 7.

STEP 6: PRIME THE ENGINE

Before starting your engine, review the safety and driving

precautions in this manual.

1) Tu rn the radio system on (transmitter then receiver). Place the

truck against a curb or some other immovable object to prevent
it from moving forward.

2) Connect the plug from the EZ-Start control box into the connec­tor mounted at the rear of the truck. The plug is keyed so it will
only insert one way. Press the start button on the EZ-Start to
turn over the engine. Do not hold for more than 5-10 seconds
to start the engine. Once the engine has started, it may be
necessary to continue to hold the start button to keep the
plug lit until the engine has warmed up.

Note: The red LED on the EZ-Start will light when the start but-

ton is pressed. This indicates that the glow plug is hot (ignit­ed). If the LED does not light, make sure that the glow plug
connector (blue wire) is firmly attached to the glow plug. If the
connection is secure, and the LED still does not light, replace
the glow plug with a Traxxas, standard plug #3230.

Primer Button

Press the primer button (built into the fuel tank) several times
until the fuel moves through the fuel line towards the carburetor.
Be sure to watch the fuel line going into the carburetor closely to
see when the fuel reaches the carburetor. Once it reaches the
carburetor, press the primer button one more time. If you press
the primer button too many times, you will flood the engine and
the EZ-Start will not be able spin it over (see page 10).

STEP 7: SHUTTING OFF THE ENGINE

Before starting the engine it is important to know how to shut it
off. The correct method is to pinch and hold the carburetor’s fuel
line at idle speed, until the engine dies.

DRIVING PRECAUTIONS

• The radio system is not waterproof.Avoid driving through puddles,
wet grass, or mud. Water could damage the electronics.

• Do not continue to operate the Nitro Stampede with low batteries.
After the battery power drops below a certain point, the model
will continue with the last command it had from the transmitter.
Indications of low battery power include slow operation and
sluggish servos. On the transmitter, a flashing red light indicates
low transmitter batteries.

• Do not drive the Nitro Stampede at night, on public streets, or
in large crowds of people.

• If the truck becomes stuck, do not continue to run the engine.

6

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3) If the engine did not start in step 2, press the primer button 3
times and retry. Continue this sequence until the engine starts.

BREAKING-IN THE ENGINE (VERY IMPORTANT!)

TRX ENGINES MUST BE BROKEN-IN FOR MAXIMUM LIFE

AND HIGHEST LEVEL OF PERFORMANCE. THIS PROCESS

MUST NOT BE SKIPPED. A SHORTCUT HERE COULD

SHORTEN THE ENGINE LIFE.

Once your engine is running, it must be broken-in. The key to

breaking in your engine is patience. The break in time will take

about 1 to 1

1

/2 hours. During the break-in period, your engine

may appear to malfunction with symptoms such as stalling,
inconsistent performance, and fouled glow plugs. Don’t give up
on it! These are just “break-in pains” that every new engine has
to go through. They will disappear once you get through the
break in period. Just keep it running, and throttle on and off

as smoothly as you can. Sudden bursts or releases of the
throttle can stall your engine. Resist the temptation to tune the

engine for performance and/or run for extended times at wide
open throttle. Soon, after about the fourth tank of fuel, your
patience will pay off with solid, consistent, performance.

Remove the obstruction before continuing to drive.

• Do not attempt to push or tow objects with the Nitro Stampede.

• The model is controlled by radio. It is subject to radio interfer-

ence from many sources beyond your control. Since radio
interference can cause momentary losses of control, allow a
safety margin around the truck in order to prevent collisions.

• Use common sense whenever you are driving your model.

Intentionally driving in an abusive and rough manner will
only result in poor performance and broken parts.

CAUTION:

DURING BREAK IN...

• Special break-in fuels are not required.

• Drive the model on a smooth hard surface.

• If possible, avoid running on very hot, humid days.

• Run with the body off for extra engine cooling.

• Do not allow the fuel tank to run completely empty, possibly
leading to a burned plug. An extremely low fuel level causes
the fuel mixture to be too lean.

•Keep extra glow plugs handy. The break-in process, because
of the engine running rich, can cause deposits to form on the
glow plug, leading to failure.

•Turn the mixture screw (needle) clockwise (in) to lean the mix­ture and counter-clockwise (out) to richen the mixture.

THE FIRST TANK OF FUEL

• Drive the Nitro Stampede on a flat paved surface in an oval con-

figuration. This will cause you to naturally vary your speed over the
entire RPM range. During this break in time, ease in and out of the
throttle slowly to avoid stalling the engine. The goal is to simply
keep the engine running.

• The fuel mixture setting may require slight adjustment to correct
for different altitudes and temperatures. To tell if the engine is running
rich (high volume of fuel flowing through the engine) look for the
following conditions:

1) The engine should accelerate sluggishly

2) There should be a thick trail of blue smoke coming
from the exhaust.

• If you do not observe the conditions above, then turn the high
speed needle out 15° (counterclockwise) and retest.

• Do not run at full speed during the first tank of fuel.

• Do not rev the engine with the wheels off the ground. High,
no-load RPMs can damage the engine, usually resulting in a
broken connecting rod. At the end of the first tank of fuel, stop
the engine and allow it to cool for 5-10 minutes before proceeding.

TANK FIVE AND BEYOND

• All final tuning adjustments must be made to the engine at its
normal operating temperature.

• The engine’s performance depends on the fuel mixture. Leaning
the fuel mixture with the high-speed needle (turning clockwise) will
increase engine power up to engine’s mechanical limits. Leaning
the fuel mixture beyond the safe allowable limits will result in poor
performance and engine damage.

• After the fourth tank of fuel, the break in process should be com­plete. Now its time to tune the engine for maximum power.

• Turn the mixture screw in (clockwise) 1/16 of a turn and continue
driving. Note any increase in speed and performance.

• Continue to lean the fuel mixture in 1/16 turn increments until :

1) There is no longer any performance increase or

2) The engine begins to cut out at high speed or

3) The engine begins to overheat. Symptoms include:

• Steam or smoke coming from the engine surfaces

• Hesitation during acceleration (as if running out of fuel)

• Popping or clattering sound when decelerating (detonation)

• The idle speed will fluctuate

• Any of the above symptoms indicate that the fuel mixture is past
the maximum safe lean setting. Turn the mixture screw back out
(counterclockwise) the previous 1/16 of a turn to reach the optimum
fuel mixture setting.

• Turn the mixture screw out another 1/16 of a turn for non-race
applications. This will extend engine component life. This setting
will vary slightly with each engine depending upon fuel brand,
temperature, humidity, etc.

High-Speed Power Loss

Overheating

LEAN

DANGER

Optimum

for High-Speed

Performance

Optimum

for Climbing

& Low Speed

Operation

RACING

EVERYDAY
RUNNING

SAFE RANGE

TANKS TWO-FOUR

2 1/2 turns out

FINE TUNING THE LOW-SPEED MIXTURE

RICH

Sluggish Performance

Break-In Settings

The low-speed mixture screw is located in the end of the throt­tle shaft (see the drawing on page 5). The low speed mixture
affects the idle quality and the low end engine power and throttle
response. To check your low speed mixture setting, perform this
simple test.

1) Drive the truck for several minutes until the engine is in its

normal operating temperature range.

2) Pull it in, stop, and listen to the idle speed. If, after a few seconds,

the idle speed begins to drop then lean the low speed mixture

2 turns out

1/8 of a turn (clockwise) and retest.

3) Continue leaning the engine in small steps until the idle speed

will stay even for at least 20-30 seconds after stopping.

Tu rn the high-speed mixture screw clockwise 150and run
through the second tank of fuel. Repeat this process for the third
and fourth tanks of fuel.

Important: Do not lean the high speed mixture less than 2
turns out from closed (see illustration). Also, be sure to
allow the engine to cool between each run.

4) The truck should accelerate quickly from a standing start with­out bogging. The idle should be smooth and consistent. Lean
the mixture 1/8 of a turn (clockwise) and re-test. If you experi­ence any stalling or hesitation when accelerating, then the low
speed mixture is too lean. Richen it 1/8 of a turn (counter
clockwise) and retest.

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

7

SETTING THE IDLE SPEED

• SHOCKS

Now that the engine mixture is tuned, the idle speed may be
set too high. Only set the idle speed when the engine is at its nor­mal operating temperature. Adjust the throttle trim on the transmit­ter so that the brake on the truck is applied. Next, reset the idle
speed by removing the air filter and adjusting the idle speed screw
on the side of the carburetor (see drawing on page 5). Turn the
screw out (counter-clockwise) to reduce the idle. Re-adjust the
throttle trim on the transmitter as necessary (so that the brake is
no longer applied). The idle should be set slow enough that the
truck does not try to move at idle.

ADJUSTMENTS

• TOE IN

Geometry and alignment specs play an important roll in your
truck’s handling, so take the time to set them correctly. Set the
steering trim on your transmitter to neutral. Now, adjust your tie
rods so that both wheels are pointing straight ahead and are par­allel to each other (0 degrees toe in). This will ensure the same
amount of steering in both directions. If you run out of adjust­ment, then the steering servo will have to be re-centered (see
“centering your servos on page 9). For increased stability add

1-2 degrees of toe in to each front wheel. Use the turnbuck­les to adjust the alignment.

Zero degrees of toe-in

• CAMBER

The camber angle of both the front and rear wheels can be
adjusted with the camber rods (upper turnbuckles). Use a square
or right-angle triangle to set the camber accurately. Adjust the
front wheels to 0 degrees of camber (wheel perpendicular to the
ground). In the rear, adjust the wheels to 1 to 2 degrees of nega­tive camber. These adjustments should be set with the truck
positioned at its normal ride height.

The four shocks on Nitro Stampede
have the most influence on its han­dling. Whenever you rebuild your
shocks, or make any changes to the
pistons, springs or oil, always do it
carefully and in pairs (front or rear).
Piston head selection depends on the
range of oil viscosities that you have
available. For example, using a two­hole piston with a lightweight oil will, at
one point, give you the same dampen­ing as a three-hole piston with heavier
oil. We recommend using the two-hole

PRE-LOAD
SPACERS

pistons with a range of oil viscosities
from 10W to 50W (available from your
hobby shop). The thinner viscosity oils
(30W or less) flow more smoothly and
are more consistent, while thicker oils
provide more dampening. Use only

100% pure silicone shock oil to
prolong seal life.

The ride height for Nitro Stampede can be adjusted by adding
or removing the clip-on spring pre-load spacers. Instead of
adding spacers to increase stiffness, use stiffer springs. Adjust
the ride height so that the suspension arms are slightly above
being parallel to the ground. Observe how Nitro Stampede han­dles in turns. If it is picking up the inside rear wheel in hard turns,
then stiffen the front suspension. If it picking up the inside front
wheel in hard turns, then stiffen the rear suspension. Proper set­up will add stability and help prevent roll-overs.

• GEAR RATIOS

A unique Nitro Stampede feature is the ability to change the
gear ratios. The final drive ratio of the gearbox is 3.75 to 1. Use
the following formula to calculate the overall ratio:

Number of Spur gear teeth

Number of Clutch bell gear teeth

x 3.75 Final drive ratio

Nitro Stampede comes with a 66-tooth spur gear and an 18­tooth pinion (clutch bell) gear. This combination will provide the
best overall acceleration and top speed. If you want more accel­eration and less top speed, then use a smaller clutch bell gear
(fewer teeth). For more top speed, use a larger clutch bell gear.

• ADJUSTING THE SLIPPER CLUTCH

The Nitro Stampede is equipped with an adjustable slipper
clutch which is built into the large spur gear. The purpose of the
slipper clutch is to regulate the amount of power sent to the rear
wheels in order to prevent rear tire spin. It also reduces the
shock transferred to the drive components when the truck is
jumped. When it slips, the slipper clutch makes a high-pitch

Positive camber Negative camber

chirping noise, which you may be able to hear over the engine

MAINTENANCE

1) Check the wheels and steering for binding. Check the operation
of the shock absorbers.

2) Check the wiring for any frayed wires or loose connections,
including the wires on the EZ-Start quick connector. Fraying
or melting of the blue wire on your EZ Start system can
cause your glow plugs to immediately short out.

3) Check the tightness of the grub screws in the collars on the
throttle and steering linkages.

4) Check the air filter for proper mounting and filtration.

5) Check the mounting of the receiver and servos.

6) Check the tightness of the wheel nuts with a wrench.

8

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

7) Check the fuel tank and all hoses for signs of leaks.

8) Check the operation of the radio system, especially the
condition of the batteries.

9) Check the exhaust system for leaks, cracks, or tears. Do not
run the model if there are any exhaust leaks.

10) Use Traxxas Nitro Wash spray cleaner to keep the model

clean of accumulated dirt and oil. Do not spray any radio
components with Nitro Wash. Do not spray Nitro Wash into
a dirty air filter while it is installed on the engine.

11) The steering servo saver will wear out over time. If the

steering becomes loose, the servo saver should be replaced.

noise. Use a 5mm wrench to turn the nut in until it stops. Now,
turn the nut back out one half turn. When running on pavement,
set the clutch so that it is tighter. When running on dirt, slightly
loosen the adjusting nut to help reduce tire spin. Do not allow the
slipper clutch to become too loose. Excess slippage is apparent
when the engine sounds fast but the truck’s acceleration is slug­gish. Excess slippage will quickly damage the slipper clutch.
The clutch should only slip for 1 or 2 feet from a standing start
on a high traction surface such as rough concrete.

CENTERING YOUR SERVOS

Whenever your radio system has been removed for service or
cleaning, the servos must be re-centered prior to installing the
radio system in the model. If the radio system is installed in the
truck, disconnect the servo horns from the servos.

Connect the steering servo to channel 1 on your receiver and
the throttle servo to channel 2. The white wire on each servo
cable is positioned towards the crystal. Connect the red and
black cable from the battery holder to the “batt” terminal on the
receiver. The red wire is positive and the black wire is negative.

Place fresh “AA” batteries in the transmitter and turn the power
switch on. Slide the throttle and steering trim adjustments to to
the center position. Now install fresh “AA” batteries into the bat­tery holder and turn the power switch to the on position. The ser­vos will automatically jump to their center positions.

Tu rn off the battery holder switch followed by the transmitter.
The servos are now ready to be installed. Be careful not to move
the servo shaft when reinstalling the servo horns.

INSTALLING A RADIO SYSTEM (Model 4104)

Before installing the radio system center your servos as
described in your radio system’s operating instructions. Note: the
plug on the Traxxas 4-cell battery holder is compatible with
Tr axxas and Futaba radio systems. Some Airtronics, Sanwa,

and Novak receivers require that the positive and negative
leads in the plug be reversed. Refer to your radio system’s

schematic to ensure that the polarity is correct.

The splines inside the steering servo saver and the throttle
servo arm are compatible with Traxxas and Futaba servos. Other
brands of servos may not fit properly and require you to pur­chase a compatible servo saver and servo arm. The designs are
an industry standard so it should not be difficult to locate identi­cal parts that will fit your servos.

Install the radio system components and hook up the linkages
as shown in the drawings on the right. Route your wires neatly to
prevent them from being damaged.

STORAGE

After running your Nitro Stampede, use a good “after-run”
product prior to storage. The chemicals used in the fuel attract
moisture and can cause moisture and corrosion to form inside
the engine. Drain the fuel tank, start the engine and run it until all
of the remaining fuel is completely used up. Remove the air
cleaner and place the recommended number of drops (usually 6
drops) of the after-run oil into the carburetor. Now, spin the engine
for 2-3 seconds with the EZ-Start to circulate the oil. Replace the
air cleaner. Never store your model with unused fuel in it.

9

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

LIMITED WARRANTY INFORMATION

Every effort has been made in component design and material
selection to make your Nitro Stampede as durable as possible.
Because the model is intended to be a hobby-class model and
operate at a much higher level of performance than a “toy,” no war­ranties can be expressed or implied relating to the longevity of the
parts. Parts will wear out and require replacement. If any part of the
model appears to be defective, or incorrectly assembled when it is
new (before it is used), it will be repaired or replaced at Traxxas’ dis­cretion.This warranty will not cover damage from wear, abuse, neglect,
crashes, or water.

• TO OBTAIN WARRANTY SERVICE

If it has been determined that your model is somehow defective,
return it to Traxxas with a note describing the problem, and a copy
of the purchase receipt or invoice. Do not return to Traxxas without
first speaking with a service technician, toll-free, at 1-888­TRAXXAS. Drain all fuel and remove all batteries. Remember that
the warranty only covers brand new products which are defective
right out of the box. All other service or exceptions will be estimated
on an individual basis.

The radio system that is provided with the ready-to-run models
is covered by separate warranty on a separate page (included in
your documentation package).The radio system warranty does not
cover water damage. Due to the special nature of the TRX Pro .15
engine, it is also covered by a separate warranty page provided with
your model.

Tr axxas reserves the right to make changes, modifications,
and improvements to this product without notification, and
which may not be reflected in these documents. Upgrades and
improvements are not necessarily retroactive.Traxxas may not

provide improved or updated components free of charge for
models built prior to any change in specification.

ENGINE TROUBLE SHOOTING

The troubleshooting guide on the following page has been pro­vided to help you in diagnosing and repairing common engine
problems. Most difficulties with engines can be traced back to
problems with adjustment, fuel quality, dirt blockage, or common
parts that wear with everyday use.

FLOODED ENGINE

The engine can become flooded if it is primed too many times
during the course of a routine start up. When the engine is flooded,
the EZ-Starter cannot turn the engine and it will appear to be
locked. Use the following procedure to clear a flooded engine.

• Remove the blue glow plug wire

• Remove the glow plug with a 5/16 nut driver

• Plug in the EZ Start and turn the truck upside down

• Push the EZ-Start button for several seconds to clear the

excess fuel from the combustion chamber

• Turn the truck over and re-install the glow plug with gasket

• Reconnect the blue glow plug wire

• Remove one of the motor wires from the EZ-Start motor

• Push the EZ-Start button for several seconds. This lights the

glow plug and burns off any remaining fuel

• Reconnect the EZ-Start motor

• Do not prime the engine. Partially open the throttle and press

the EZ-Start button. The engine should start immediately.

GLOW PLUGS

Be sure to include a return address and a daytime phone number.
MAIL OR SHIP TO:

TRAXXAS

1100 KLEIN ROAD

PLANO, TEXAS 75074

For technical assistance regarding your model,
call (888) TRAXXAS (872-9927),
972-265-8000 (outside of the U.S.A.),
or E-Mail Traxxas at [e-mail]
For orders and other information,
call 972-265-8000 or fax [phone].

while pressing the EZ-Start button. The glow plug will not light
unless it is grounded against the engine. Glow plugs can be
damaged by particles in the combustion chamber or by running
the fuel mixture excessively lean.

Tr axxas makes 2 glow plugs. The standard hot plug
(part#3230) is the stock replacement plug for Traxxas engines.
The optional heavy-duty plug (part#3231) will last longer in most
cases however, it is a medium temperature plug so performance
may be reduced slightly. Do not use plugs with idle bars!

CARBURETOR

Dirt is the main enemy to your carburetor. If you notice a sud­den change in the fuel mixture (lean) and performance of your
model, you may have dirt lodged in the carburetor. To dislodge a
dirt particle in your carburetor try screwing the high and low
speed needles all the way in and then back out to their original
settings. If the engine doesn’t return to normal operation, then try
backing the mixture screws out and prime the engine to force
fuel through the carburetor. Return the mixture screws back to
their original settings. The engine will be flooded at this point so
follow the directions for relieving a flooded engine. If this fails,
then the carburetor will need to be removed and cleaned with
Tr axxas Nitro Wash or denatured alcohol. Do not blow on carbu­retor passages or fuel lines with your mouth. Fuel and solvents
are extremely poisonous. To prevent this from occurring again,
insert a fuel filter in the line between the tank and the carburetor.

EZ-START

The glow plug in your engine is a consumable item which
must be replaced periodically to maintain peak performance and
starting ease. To test for a leaking glow plug, place a few drops
of fuel around the the base of the glow plug when the engine is
cool. With the engine running, look for bubbles around the glow
plug. If the gasket is leaking, tighten the plug or replace the gas­ket.

The EZ-Start control box has an LED which lights to indicate
the condition of the glow plug. If the LED does not light when the
button is pressed, then the glow plug element is broken.
However, glow plug performance can deteriorate significantly
before the element actually burns in two. The only sure way to

test for a faulty glow plug is to replace it with a new one to
see if the problem goes away. You can view the glow plug

element by removing it and touching it against the engine head

10

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

The battery to the EZ-Start must be fully charged for the best
performance. If the battery is weak, the EZ-Start may appear to
be spinning the engine fast enough to start however, there is not
enough current to adequately light the glow plug. If the EZ-Start
appears to spin normally, but doesn’t seem to “catch” and spin
the engine adequately, then inspect the one way bearing inside
the starter. If it becomes saturated with castor oil from the engine
fuel, then it will slip on the starter shaft. Clean or replace the one
way bearing. If there is excessive gear noise, then suspect broken
gears inside the EZ-Starter. If the EZ-Start motor spins freely
with no gear noise, then the motor pinion gear may be stripped. If
this occurs, then the EZ-Start motor assembly must be replaced.
The pinion gear is pressed on, and not available separately.

ENGINE TROUBLESHOOTING GUIDE

Engine will not start 1 3 7 28 8 16 13 14 21 29 19 39 40 36

EZ-Start motor will not turn 8 10 17

EZ-Start turns but engine does not 11 12 41

Engine starts and then stalls 16 21 27 24 29 28 30 36

Engine sluggish, poor performance 3 6 16 15 21 24 26 22 20 32 34 33 38 35 36

Engine Overheats 3 4 5 6 21 25 23 28 29 37 38 35

Engine chokes/hesitates at speed 1 2 16 21 23 28 29 30 20 31

Engine stalls under hard acceleration 1 2 16 21 24 25 26 27 28 29

Engine stalls around turns 1 2 30

Engine stalls during normal driving 1 2 3 16 28 29 30 21 20 36

1Out of fuel ........................................................ Fill fuel tank

2 Fuel level is low ................................................ Refill fuel tank

3 Improper or contaminated fuel ........................ Replace fuel

4 Excessive nitro in the fuel ................................ Use fuel with a lower nitro content (page 2)

5 Incorrect oil content in the fuel ........................ Switch to a recommended brand of fuel (page 2)

6Poor Quality fuel .............................................. Switch to a recommended brand of fuel (page 2)

7 Engine not primed ............................................ Prime engine (page 6)

8 EZ-Start battery not charged ............................ Use a freshly-charged battery (page 3)

9 EZ-Start ground wire (yellow) faulty ................ Clean, tighten, or replace ground wire (page 12)

10 EZ-Start Motor wire loose ................................ Check motor connections on the EZ-Start motor

11 One-way starter bearing slipping...................... Remove EZ-Start/ Clean or replace bearing (page 12)

12 EZ-Start gears damaged .................................. Listen for excessive gear noise/ Replace gears/motor.

13 Glow plug wire loose from glow plug................ Crimp the connector on the glow plug wire

14 Glow plug wire damaged .................................. Replace or repair glow plug wire

15 Leaking glow plug gasket ................................ Check glow plug gasket/ tighten glow plug

16 Glow plug fouled or weak ................................ Check for a solid red light when the EZ-start button is

pressed/ No light indicates a completely shorted plug/

Replace with Traxxas 3230 or 3231 glow plugs (page 10)

17 Engine flooded .................................................. Clear the engine of excess fuel (page 10)

18 Engine overheated............................................ Allow engine to cool- find cause for overheating

19 Exhaust blocked .............................................. Clear any obstructions

20 Air cleaner plugged .......................................... Clean and replace air cleaner element (page 5)

21 Carburetor incorrectly adjusted ........................ Readjust carburetor to factory break-in settings (page 5)

22 High-speed fuel mixture is too rich .................. Lean the high-speed mixture (page 7)

23 High-speed fuel mixture is too lean .................. Richen the high-speed mixture (page 7)

24 Low speed mixture misadjusted ...................... Fine tune the low speed mixture adjustment (page 7)

25 Low speed mixture too lean ............................ Richen the low speed mixture adjustment (page 7)

26 Low speed mixture too rich .............................. Lean the low speed mixture adjustment (page 7)

27 Idle speed set too low ...................................... Increase idle speed (page 8)

28 Fuel flow blocked .............................................. Check that all fuel lines are clear with no pin-hole leaks

Check for dirt blockage in the carburetor fuel inlet and

high-speed needle seat/ Install inline fuel filter (page 10)

29 Air bubble in the fuel line .................................. Prime the engine to force the air through/ Check for pin-

hole leaks in the fuel line

30 Insufficient fuel tank pressure .......................... Replace the pressure hose (between pipe and fuel

tank)/ clear blockage in the tuned pipe hose fitting/

check flow to and from tank/ Check fuel tank cap seal

31 Engine overheated............................................ Allow engine to cool/ find cause for overheating

32 Slipper clutch loose .......................................... Tighten the slipper clutch (page 8)

33 Engine overgeared for application .................... Use a lower gear ratio (page 8)

34 Engine clutch slipping ...................................... Replace clutch shoes (see engine repair section, page 13)

35 Drive system is bound ...................................... Locate the bound item and repair

36 Engine excessively worn .................................. Repair or replace engine (page 12)

37 Cooling air to the head is blocked .................... Cut ventilation holes in the body (windshield)

38 Excessive load on the engine .......................... Check for bound drivetrain

39 Broken clutch shoe spring ................................ Replace clutch shoe spring (page 13)

40 Loose flywheel .................................................. Replace flywheel nut (page 13)

41 EZ-Start motor pinion stripped .......................... Replace EZ-Start motor

Contact Traxxas for assistance: 1-888-TRAXXAS. 972-265-8000 (outside USA). E-Mail us at [e-mail]

11

STEP 9: Changing the piston and sleeve assembly

Use a 5/16 inch nut driver to remove the glow plug and

copper gasket.

STEP 10:

Use a 2.5mm allen wrench to remove the four 3x12mm

cap head screws that fasten the cylinder head. Rock

the cylinder head gently from side to side to release it

from the sleeve. Note the thin aluminum head gaskets.

We recommend that you replace these gaskets with

new ones upon reassembly.

STEP 11:

Remove the backplate and the

starter shaft. Replace the backplate

gasket with a new one during

assembly.

STEP 12:

The piston and sleeve are a matched set. When the

piston and sleeve are disassembled, they must be

reassembled in the same orientation. Use a hobby

knife to scratch a mark to indicate the location of the

piston in relation to the pinning of the sleeve.

12

STEP 7:

To separate the engine from the engine mount,

remove the four 3x10mm caphead machine screws.

* Note: You will not need to remove the engine mount

for a basic rebuild of the engine. Do remove the engine

mount if you are exchanging the engine under the

Lifetime Engine Replacement Plan.

REBUILDING THE ENGINE

STEP 1:

Disconnect the red and black wires from the EZ-Start

motor. Remove the EZ-Start gearbox by removing the

three 3x8mm roundhead machine screws.

STEP 8:

Removing the carburetor is not necessary to rebuild

the engine, unless you intend to replace the internal

bearings of the engine. Remove the carburetor by

loosening the 3mm locknut and pulling the carburetor

straight up.

STEP 2:

Unplug the blue wire from the glow plug. Remove the

fuel line from the carburetor inlet and from the exhaust

header pressure fitting.

STEP 3:

Use a 2.5mm hex driver to remove the yellow ground

wire from the engine mount. Move the EZ Start wiring

harness out of the way.

STEP 4:

Use a 2.5mm hex driver to remove the four 3x10mm

caphead machine screws from the engine mount.

STEP 5:

Pull the engine from the chassis.

Remove the exhaust tube from the

header. Turn the engine so that the

throttle linkage to the carburetor will

come out.

STEP 6:

Remove the 3x23mm roundhead machine screws that

fasten the header to the engine. Remove the header

and the old gasket. Replace the header gasket with a

new one during assembly.

13

STEP 15:

Remove the connecting rod and piston through the top

of the crankcase.

STEP 16:

To remove the connecting rod from the piston, use a

sharp-pointed tool to remove the small metal G-clip in

the side of the piston. Do not re-use the old G-clip.

When installing a new connecting rod, use the sup-

plied new G-clip.

STEP 21:

Remove the crankshaft by pulling it straight out of the

crankcase.

STEP 22:

The bearings are press-fit into the crankcase. To

remove them, the crankcase must be heated with a

heat gun or torch. The crankcase will expand with heat

and release the bearings. To avoid the possibility of

burns or other damage, do not attempt remove the

bearings. Clean the bearings by flushing them with

denatured alcohol and then place one or two drops of

after-run oil on the races.

STEP 23:

Before installing a new connecting rod, you can

increase connecting rod life by polishing the crank-

shaft journal. Use 1200 grit sandpaper to remove the

surface scratches followed by liquid metal polish to

buff the crankshaft journal to a bright, smooth shine.

Rinse thoroughly with Traxxas Nitro Wash or dena-

tured alcohol. Lube with after-run oil.

STEP 24:

Use the 1200 grit sandpaper and the liquid metal pol-

ish on the wrist pin also. Rinse thoroughly with dena-

tured alcohol and lube with after-run oil.

STEP 13:

Pull the sleeve straight up and out of the crankcase. If

the sleeve will not move, rotate the crankshaft until the

sleeve pushes up.

STEP 14:

Rotate the crankshaft to bottom dead center. Lightly

grab the connecting rod with a pair of needlenose pli-

ers and gently pull it off of the crankshaft journal.

STEP 17: Removing the clutch and flywheel

It is not necessary to remove the clutch assembly

unless you are servicing the clutch, crankshaft, or

engine bearings. Use the tip of a small screwdriver to

remove the E-clip which holds the clutch bell gear.

shoes for excessive wear or

cracking around the pin

holes. If the clutch shoes

are worn to the point that

the clutch spring contacts

the clutch bell, then the

shoes must be replaced.

STEP 19:

Grip the flywheel with a pair

of pliers (locking pliers work

best). Remove the clutch

adapter nut with a 10mm

deep socket. Hold the

engine just above your

workbench and tap the fly-

wheel from behind with a

non-marring hammer (plastic or wood). Several easy

blows may be necessary to release the flywheel and

split beveled cone.

STEP 20:

The flywheel and the split-beveled cone should pull

smoothly off of the crankshaft.

STEP 18:

Remove the clutch bell gear and the clutch shoes.

Note that there are two 5x8mm PTFE washers, one on

each side of the clutch bell gear. Check the clutch

STEP 36:

Reinstall the carburetor with a new o-ring, header, a

NEW glowplug, and engine mount. Use a new header

gasket when re-installing the header on the engine.

Reinstall the engine in the truck in the reverse order

of removal. Don’t forget to reconnect the yellow

grounding wire to the engine mount. The rebuilt

engine must now be broken in.

STEP 31:

Reinstall the backplate and a new backplate gasket

with the 3x8mm caphead machine screws. Tighten the

screws in small increments, in a criss-cross pattern

until all the screws are tight.

STEP 32:

Install the appropriate size ball bearing into one side of

the clutch bell gear. The Nitro Stampede comes stock

with an 18-tooth clutch bell gear which requires

5x11mm ball bearings.

STEP 33:

Tu rn the gear over and install the other ball bearing.

STEP 34:

Install the split-beveled cone onto the crankshaft. Next,

install the flywheel. Install the clutch adapter nut with a

10mm deep socket. Grip

the flywheel with pliers

while tightening the

adapter nut.

STEP 25:

To assemble the connecting rod and piston, place a

drop of caster oil in the top end of the connecting rod.

Insert the wrist pin through the piston and the top of

the connecting rod. Secure the wrist pin with the G-

clip. Make sure the G-clip fits securely into the groove

machined in the piston. Be careful not to scratch the

sides of the piston.

STEP 26:

Reinstall the crankshaft into the engine and make sure

that it spins freely. Insert the connecting rod and piston

assembly through the top of the crankcase. The G-clip

should face the carburetor. Put a drop of castor or

after-run oil in the bottom end of the connecting rod.

Use your fingers to gently push the end of the con-

necting rod over the crankshaft journal.

STEP 27:

Place another drop of oil on the connecting rod bush-

ing. Rotate the crankshaft several times to distribute

the oil.

STEP 28:

Insert the sleeve into the top of the crankcase. Rotate

the sleeve so that the notch in the sleeve will line up

with the pin in the crankcase. Holding the engine

upside down will make it easier for the sleeve to go

over the piston.

STEP 29:

Install new head gaskets on the head. Use one thick

and one thin gasket. Reinstall the head using the

3x12mm caphead machine screws.Tighten the screws

in small increments, in a criss-cross pattern, until all

the screws are tight.

STEP 30:

Reinstall the starter shaft. Align the notch in the starter

shaft with the crankshaft journal pin (arrow).

14

STEP 35:

Install the clutch shoes

exactly as shown in the

drawing (leading edge

engagement). Next, install

a 5x8mm PTFE washer

followed by the clutch bell

gear (with bearings

installed). Install the

remaining 5x8mm PTFE

washer followed by the E-

clip (see step 14).