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LoW SPEED nEEDLE VaLVE:
The low speed needle valve is preset from the factory for the initial starting procedure.
Do
not make adjustments to it at this time.
The low speed needle valve meters the air/fuel
mixture at idle and during transition from idle to full throttle. Turn the low speed needle
valve clockwise to lean the mixture. Turn the low speed needle valve counterclockwise
to richen the mixture. The low speed needle valve is preset from the factory, but minor
adjustments may need to be made to suit your application: fuel used, glow plug and
environment all contribute to the setting.
Do NoT aDJUST ThE low SpEED NEEDlE
VaLVE UnTiL afTEr THE EnginE HaS bEEn broKEn in.
if you need to reset the low speed needle valve to the factory setting, follow these simple procedures:
●
Open the carburettor barrel completely.
●
While holding the carburettor barrel open with your fingers, use a flat blade screwdriver to turn the low speed needle valve
clockwise until it stops. Do not force it. From this point, turn the low speed needle valve counterclockwise
3 full turns.
This
is the factory setting.
iMPorTanT TiP aboUT rESETTing THE LoW SPEED nEEDLE VaLVE
iDLE SToP SCrEW:
The idle stop screw adjusts the closure of the carburettor barrel. We recommend that
the idle stop screw be adjusted so that the carburettor barrel stays open about /6"
(mm). Turning the screw clockwise will cause the barrel to stay open more. Turning
the screw counterclockwise will allow the barrel to close more. If the carburettor barrel
stays open too far, the engine will idle very high and the clutch will never disengage. This
will damage the clutch very quickly. If the idle stop screw is closed too far, the engine
may die during idle. Ideally, the engine should idle smoothly, yet slow enough so
that the clutch stays disengaged.
HigH SPEED nEEDLE VaLVE:
The high speed needle valve is preset from the factory for the initial starting procedure.
Do
not make adjustments to it at this time.
The high speed needle valve is used to meter
the air/fuel mixture at full throttle. Turn the needle valve clockwise to lean the mixture or
turn the needle valve counterclockwise to richen the mixture.
THE faCTory SETTing for THE HigH SPEED nEEDLE VaLVE iS 3.5 TUrnS oUT
froM boTToM (fULLy CLoSED).
Check to ensure that the high speed needle is set at
3.5 full turns out from closed before commencing run-in.
fUELing anD STarTing THE XTM raCing 24.7 niTro EnginE
If at any time the pull-starter becomes very tight or difficult to pull -
SToP!
The engine has become flooded and the excess
fuel
must be removed from the engine
or damage to the pull-starter and/or engine could occur. To remove the excess fuel
from the engine follow the procedures listed below:
●
Completely close the high speed needle valve until it bottoms out. Do this gently. Don't force it!
●
Remove the glow plug and washer from the cylinder head.
●
With a rag over the top of the engine, pull the pull-starter cord several times to expel the excess fuel from the engine.
●
Check to make sure that the glow plug has not been fouled, then reinstall it and its washer.
●
Reset the high speed needle valve 3.5 full turns out from bottom (fully closed).
Warning!! PLEaSE rEaD THiS bEforE STarTing yoUr EnginE for THE firST TiME!!
Warning
Under no circumstances should you operate the engine without the air filter installed on the carburettor. The air filter prevents
dust and debris from entering the engine and damaging it. If you operate your engine at any time without the air filter installed, the engine
will not be covered under warranty should it need repair.
Continued on next Page
Summary of Contents for XT2 Racer
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