How To: Return the needle settings on a HBI 21BB engine

Return the needle settings on a HBI 21BB engine

In this video tutorial, viewers learn how to return the base settings on a HPI 21BB engine. The engine has 3 needles carburetor: high speed, mid-range and low speed. Begin by turning the high speed needle clockwise until it is closed. Then turn it 3 1/2 turn counterclockwise. Then turn the mid-range needle clockwise until it is closed. Then turn it 3 1/4 turn counterclockwise. When adjusting the low range, make sure to hold the mid-rang with a screwdriver to prevent it from turning. Now turn the low range needle clockwise until it is closed. Then turn it 3 1/2 turn counterclockwise. This video will benefit those viewers who have an HPI 21BB engine, and would like to learn how to return it to the needle settings.

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