Pilot Screw Adjustment

Idle Drop Procedure


If the engine must be running to do some work, make sure the area is well ventilated. Never run the engine in an enclosed area. The exhaust contains poisonous carbon monoxide gas that may cause loss of consciousness and lead to death.

■ Make sure the carburetor synchronization is within specification before pilot screw adjustment (see page 1-6).

■ The pilot screws are factory pre-setand no adjustment is necessary unless the pilot screws are replaced. Use a tachometer with graduations of 50 rpm change.

Remove the maintenance lid (page 2-3).

Pilot screw wrench 49 state and California type: 07KMA-MN90100 or 07MMA-MV9010A Canada type: 07908-4730001

1 . Turn each pilot screw clockwise until it seats lightly, then back it out to the specification given. This Is an initial setting prior to the final pilol screw adjustment.


Damage to the pilot screw seat will occur if the pilot screw is tightened against the seat.

Initial Opening: 49-states type:2-1, 8 turns out : California type: 2-3/4 turns out : Canada type: 2 turns out

2. Warm up the engine to operating temperature Stop and go riding for 10 minutes is sufficient.

3. Attach a tachometer according to its manufacturer's instructions.

4. Adjust the idle speed to the specified rpm with the throttle stop screw.

Idle Speed: 49-states and Canada type: 1,200 ± 100 rpm : California type; 1,400 + 100 rpm

5. Turn all pilot screws 1 /2 turn counterclockwise from the initial setting.

6. If the engine speed increases by 50 rpm or more, turn all pifot screws out by successive 1/2 turn increments until engine speed does not increase

7. Adjust the idle speed with the throttle stop screw.

8. Turn the No. 3 carburetor pilot screw in until the engine speed drops 50 rpm.

9. Then turn the No. 3 carburetor pilot screw counterclockwise 1/2 turn from the position obtained in step 8.

10. Adjust the idle speed with the throttle stop screw.

11. Perform steps 8, 9 and 10 for the No. 1, 2 and 4 carburetor pilot screws.



07kma Mn90100



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