How to Do a Back Flip on a BMX Bike. Part of the series: BMX Tips & Tricks. Back flips on BMX bikes are best attempted on a full ramp, which propels the bike at the right angle to completely the rotation. Practice back flips on a soft landing before moving on to hard landings with help from a professional BMX competitor in this free video on BMX tricks. Read more: http://www.ehow.com/video_6191264_do-...