With the 9 O'clock, or 90 degree, release as you hold the bowling ball your hand is turned horizontally to the side facing 9 O'clock. This release causes the ball to have a lot of spin. It sometimes causes what we call a spinner. This means the bowling ball is spinning like a top. It also has very little ball to lane surface contact.
This means the bowling ball will not have much hook or drive as it rolls down the bowling lane. When it hits the bowling pins it may hit dead with not much action. (Note: this is also called the 90 degree axis rotation). Other names for this are the helicopter" or "UFO" delivery, which is popular in Asia, PBA Member Butch Soper uses this type ball motions.
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