Universal Parts Carburetor Air Adjustment Spring for 50cc 4-stroke QMB139 engines.
Is your scooter stalling at red lights or surging unpredictably? A weak or corroded idle screw spring fails to hold your carburetor’s adjustment under engine vibration, leading to constant tuning headaches. This Universal Parts Air Adjustment Spring provides the precise tension needed to lock in your fuel mixture and restore a smooth, reliable idle.
