A detailed explanation from another poster last year.
"Well after all the debate about crankers v. strokers, and how seemingly
strokers don't give crankers much deference, I would like to indicate how some of us crankers rev the ball and just how much effort it takes to do so. Maybe then you strokers will understand why we are not as accurate.This is not the only way to rev the ball, its just how I do it. A lot of others have different overall styles, however, they will use similar parts in their game to obtain a high revolution rate.
First and foremost, your legs are your foundation. Legs provide you with stability and balance, thus allowing a bowler to utilize and transfer power from the legs to the release point. Proper knee bend is critical, however, it doesn't mean that you have to "get low." There is a point where if you get too low you will lose your leverage which will result in loss of revs. Everyone has a different point so no two knee bends will be exactly the same. Examples, Ryan Shaffer with his stiff knee pop up style and Robert Smith with his deep knee bend style.
Crankers have a cupped wrist. They may open it up at the backswing, however, before release their wrist is cupped.
Next, crankers open up the shoulders to get more leverage on the ball. Ala Amletto, Robert, Rudy, Couch.
Next, crankers make a slight forward movement of the hips while closing
their shoulders. This slight forward movement of the hips and closing of the shoulders adds to the power in the release.
Next, most crankers create a flat spot in their release. This flat spot
is right before the ball reaches the side of the body. During this flat spot, some bowlers will bend their elbow to create the flat spot, and other will keep a straight elbow but slide more to create the flat spot.
Typically,the bowlers that plant, grip and rip bend their elbows more and the
ones with the straight elbows slide more. A flat spot is necessary for the
bowler to get under or around the ball and it also serves as a intitiator in getting the ball off the bowlers hand. Again, this flat spot is right before the ball reaches the side of the bowler's body.
A great example of a bowler that uses a highly pronounced flat spot is
Chris Barnes. Great form and gets a good amount of turn on the ball. Barnes has a powerful release which is greatly created by the flat spot he incorporates into his style.
Next is the release point. This entails uncocking the wrist and then
cocking it back ending with lifting through with the fingers. The whole release point at maximum leverage is end the end of the flat spot (when the ball reaches the side of the body) to the point where the ball reaches the plant foot. From the time it takes the ball to go from the side of a bowler's body to the plant foot, the bowler must release the ball which comprises uncocking the wrist, cocking it back, and then lifting with the fingers. In order to do this properly, a bowler must have a quick wrist.
I am not going to get into the trail leg position because its rather
obvious where it should be.
Well that about wraps up the major components of turning up a ball. Next time you see a cranker (a real one not a wannabe kid), think of all the things that he/she must do to get all those revs. And realize that the cranker created that area on the lane so you shouldn't be jealous of that area. With all this extra effort put into releasing a ball, the payoff is area and the sacrifice is accuracy. Yes we won't be as accurate, but we will have created area to make up for that loss of accuracy. By area I mean lane area as well as pocket area. And of course, with proper dressing of the lanes, our area can be taken away. Strokers will always have a chance so be glad that you have your chance and let us cranker bowl in peace.
In case some of you need an analogy, think of cranking a ball like racking a whip. The handle being the bowlers leg. The handle must be solid and stable. The whip is like the bowlers hand. It must cup, uncock and then cock back to get that snap. Just like a whip how the whip makes its sinusoidal like figure before cracking, the end of the whip being like the bowlers fingers.
Or, how about comparing it to a basketball shot, except that bowling is
underhand. Think of how the basketball player's wrist is used to put spinon the ball. That is how a cranker uses their wrist to also turn the ball, except that bowlers are underhanded.
With regards to Bowlerbuf, a quick wrist is necessary. That is how small people like Amletto and Hoskins can rev up the ball. They do not have the physical strength like you, but they can turn up a ball more than 99% of bowlers out there due to their quick wrist. Another example is Michelle Feldman. I bet she can turn up the ball more than 99% of people here men included. Yet I bet her hand is much smaller in span. I belive its in the upper 3" something range. She is an example of a bowler with a quick wrist.
Bowlerbuf, you said that you have to back off the thumb for more revs, you need to do this because you do not have a quick wrist. Backing off the thumb allows a bowler to get the ball of their hand quicker which is necessary for more revs. However, someone with a quick wrist doesn't need to back off the thumb in order to get the ball to fly off their hand.
With proper technique, a bowler can rev up a ball. Yes some power is
necessary, however, proper technique is essential to cranking it up.
In conclusion, for a high revolution rate, a cranker opens the shoulders, plants (some with minimal slide), closes the shoulders, moves hips forward, creates a flat spot in their armswing, uncocks the wrist, cocks it back and lifts through with the fingers."
