Description Of The Acv (Air Cut Valve) System - KTM 2003 950 Adventure Repair Manual

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Description of the ACV (air cut valve) system

ACV stands for Air Cut Valve.
The ACV system enriches the mixture by reducing the idle-air quantity
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to prevent the exhaust from backfiring in an overrun condition or upon
sudden closure of the throttle valve.
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Normally the required idle-air reaches the mixture through two air jets,
the idle air jet (jet diameter 50) and the ACV jet (jet diameter
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80).
In an overrun condition or during upon sudden closure of the throttle
valve, the momentary high under-pressure causes the diaphragm of
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the ACV valve to close the air channel to the idle-air jet against the
pressure of the ACV spring . Now the air can only be drawn in
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through the ACV jet , resulting in a richer mixture.
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The system needs no maintenance. No servicing is required other than
an inspection of the components when the carburetor is overhauled. No
adjustments can be made.
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