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Fine settings of idle and full throttle are only possible with the engine well run-in. Only perform adjustments
at the carburettor when the engine has run for at least 2 - 3 hours.
When performing settings, only adjust the screws at the carburettor in very small steps (max. 1/16 turn) and
record the changes or rotating direction.
Then test the new setting to see if it has any benefits as compared to the previous one. Only proceeding
carefully permits easy reversal of bad settings.
If you have never set a RC model car carburettor before, ask an experienced model sportsman before you
perform any settings. Improperly set carburettors are the main reason for starting problems of the motor.
Description of the carburettor parts (see figure on the last page):
1 = Mix adjustment screw (Main jet needle)
The mix adjustment screw is located above the fuel outlet (2). It regulates the air/fuel mix by full throttle.
Turn the screw clockwise to „thin“ the mixture (to reduce the fuel component of the mixture) and anti-clockwise to
make the mix „richer“ (to increase the fuel component).
The default setting is with the screw turned in/out until it is flush with the edge of the nozzle holder (screw does not
protrude over the edge and is not deep in the nozzle holder).
2 = Fuel connection for tank
This connection is connected to the tank via a hose. There is, e.g., a tank pendulum in the tank so that the fuel is
always sucked in from the bottom-most position in the tank and the tank can be nearly emptied.
3 = Throttle stop screw (idle adjustment screw)
The throttle stop screw is the small screw below the air intake opening (3); it regulates the position of the carburettor
slide (the throttle stop) and thus the carburettor passage at idle speed.
One clockwise turn of the adjustment screw increases the throughput and increase the engine speed; one counter-
clockwise turn retracts the slide further and thus reduces the gap and thus the engine speed.
We recommend a carburettor outlet of approximately 1 - 1.5 mm as a basic setting.
4 = Connection to the Motor
The carburettor is connected to the combustion engine here and the fuel-air mix is taken to the combustion cham-
ber.
5 = Idle mix adjusting screw
The idle speed mix adjusting screw is the small screw on the side of the carburettor linkage. It regulates the air/fuel
mix when idle and in the transition interval to full throttle.
Turn the screw clockwise to „thin“ the mixture (to reduce the fuel component of the mixture) and anti-clockwise to
make the mix „richer“ (to increase the fuel component).
In order to reset the factory setting, open the carburettor slider completely first. Keep the slide open and turn the idle
speed mix adjusting screw clockwise until it stops. Now unscrew turning it by 3 rotations anticlockwise.
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