Re: Power clean, warm-up to max
You don't give yourself much time to set your back before you lift. During the lift you aren't keeping your back set either.
You are consistently bending your arms early.
Your weight shifts forward on to the balls of your feet as the bar comes off the ground.
Those shoes are a terrible choice to practice the clean; you're floating all over the place in them. Do you have any hiking boots? Cowboy boots? Bowling shoes? Weightlifting shoes?
Here's what you need to work on:
Set your back before you lift. Keep it set.
Keep the arms long.
Keep your weight on your heels.
Wear better shoes; something with a firm sole and a bit of a hard heel.