Xray NT18 0.8cc, Инструкция и руководство по безопасности

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Main Needle Adjustment
When the main needle is properly adjusted, the engine immediately responds to the throttle operation with clean, hard
acceleration without hesitation.
To check if the engine is running at a proper setting, pinch the fuel line to the carburetor and observe the results:
• At a proper setting, the engine RPM increases instantly then the engine dies out.
• If engine dies out immediately without increasing RPM, the main needle setting is too lean.
Low-End Needle Adjustment
The most difficult thing to adjust is the low-speed adjustment. Keep the following principles in mind when doing this:
• Use the idle adjustment screw to adjust the idle RPM immediately after closing the carburetor.
• Use the low-speed needle to adjust the fuel mixture 2-5 seconds after closing the carburetor.
• Use only a ½ turn each way.
The low-end needle of each individual engine is precisely adjusted at the factory. The low-end needle adjusts the performance
of the engine between idle up to approximately ¼ throttle. Above ¼ throttle the main needle has the most effect on engine
performance.
CARBURETOR ADJUSTMENT – BEFORE PUTTING THE CAR ON THE TRACK
After the engine is running and has come up to operating temperature (within 15-20 seconds) proceed as follows:
Stage 1: Setting the Main Needle Slightly Rich
Take the car off the ground, and open the throttle fully. The engine should run cleanly until it
reaches 80% of top RPM, after which it should start to run slightly rich (4-stroking):
• If the engine runs cleanly all the way up to top RPM, richen the main needle (counter-
clockwise) until it starts to 4-stroke at approximately 80% of its top RPM
• If the engine runs too rich (4-stroking all the way) lean the main needle (clockwise) until
it only starts to 4-stroke at approximately 80% of its top RPM
Adjust main
needle valve