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Carburetor Idle Adjustment

What you need

  1. Carburetor Idle Adjustment, Carburetor Idle Adjustment: step 1, image 1 of 2 Carburetor Idle Adjustment, Carburetor Idle Adjustment: step 1, image 2 of 2
    • Use a 3/8 socket wrench to loosen the retaining bolts on the air cleaner.

    • Rotate the air cleaner so that the throats of both carburetors are clear. Now you will be able to adjust them.

    • Start the engine

  2. Carburetor Idle Adjustment: step 2, image 1 of 2 Carburetor Idle Adjustment: step 2, image 2 of 2
    • Allow time for the engine to warm up completely

    • Attach carburetor synchronization tool to one of the carburetors

    • Observe the relative reading, and remember it.

    • This reading is a measurement of the airflow speed

  3. Carburetor Idle Adjustment: step 3, image 1 of 1
    • Set the synchronization device on the other carburetor.

    • Using a Flathead screw-driver, twist the idle speed screw in to raise the flow, and out to lower it.

    • Recheck both carburetors and adjust as needed to get the flow as equal as possible.

  4. Carburetor Idle Adjustment: step 4, image 1 of 2 Carburetor Idle Adjustment: step 4, image 2 of 2
    • Now, the idle mixture screws must be adjusted.

    • It is important that when the screws are adjusted they are adjusted the same amount in the same direction.

    • Turn both screws in, or out an 1/8 or a turn at a time until the fastest idle speed is achieved.

    • Before proceeding with this step you should have already checked your ignition timing, if you have not do it now, and then continue from here.

  5. Carburetor Idle Adjustment: step 5, image 1 of 1
    • Finally, raise or lower the idle speed screws until the idle speed is about 550 RPM

    • Once more, it is important to adjust the screws the same amount.

    • Rotate the aircleaner back to its original position, and re-tighten the 3/8 nuts on the retainers

Noah

Member since: 10/03/12

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Team

Cal Poly, Team 6-33, Regan Fall 2012 Member of Cal Poly, Team 6-33, Regan Fall 2012

CPSU-REGAN-F12S6G33

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