lunge punch control

[B&D]

I had a good evenings training last night, what I did realise was an issue I had with the above move. when executing the punch I always had to take another small step after the punch to counter excess momentum. I could not control my momentum after the punch, I understand that this means my kime was not correct, what I want is to understand where i'm going wrong eg is it too short a step, too high, going forward with upper body, please can the high grades tell me next training session or maybe give me an idea using the forum.

[Moley]

Upper body too far forward hence momentum continues. Think of all that weight leaning forward when you come to a sudden stop. Like slamming your brakes when you are on a racing bike with drop handlebars. You go over the handlebars and land on your head.
Try to lean back in your attacks so that you are sitting back in a chopper style bike like Cheungy's.