The ideal tap position would be directly under the high bar, followed by quickly and forcefully kicking your toes up and over the bar in a hollow position. You may be shifting your wrists too early--that'll cause you to put the brakes on and miss the giant. I suggest trying to shift your wrists later and concentrate on coming over the top hollow with your toes first.
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try tapping right under the lower bar. Watch your feet pass by the low bar and then tap and make sure to flick your wrists. Also, make sure you have a high cast. The higher the cast the easier the giant.
1. cast to handstand, the first time you do it you have to wait as you fall longer
2. come down and watch the low bar
3. be in a hollow position if you are arched, you'll never make it
4. tap underneath the low bar, think of it as a tight arch
5. flick your lower body in a hollow position around the bar
6. shift your wrists late, DO NOT: -let your head come out, -arch around, or -let your elbows lock b/c you can get hurt