2006 Arctic Cat DVX 400 Service Manual, Page 19Get this manual
Adjusting Engine RPM (Idle)
To properly adjust the idle RPM, tachometer is necessaryTo adjust idle RPM, use the following procedure1With the transmission in neutral, start the engine and warm it up to normal operating temperature2Turn the idle adjustment screw (on the left side of the carburetor) clockwise one turn past the recommended RPM setting; then turn it counterclockwise to 1250-1350 RPMSP016A
3Place drain pans under the oil tank drain plug (1) and the crankcase drain plug (2); then remove the plugs and drain the oil
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