How to test ZF Factory IWC Portugieser IW390302 Super Clone Watch flyback reset function

Testing flyback on this ZF Factory IWC Portugieser IW390302 Super Clone Watch is easy. Press the 2 o’clock button to start chrono. After the hand runs about ten seconds, don’t pause, just press the 4 o’clock reset button all the way in. If the big chrono second hand snaps back to zero and instantly restarts with no gap, hands line up tight, no clear stick or shake, then flyback is fully good. As a more complex IWC Portugieser flyback replica watch, just test once or twice when checking to confirm clean snap back. Don’t keep mashing it hard normally, or you’ll damage the movement chrono lever.