Hi Lefty,
Thanks for responding. I'll try to describe what I understand :
- If the ball has no side-weight, it'll go almost strait, am I right ?
- The quantity of side weight will dictate the ball path isn't it ?
- When you give additionnal skid in the ball, do we still call it the End over end roll ?
- In heavy oil pattern, can we use the term of end over end roll when we use pearl or shinny ball (these balls normaly skid in oil) ?
One again thanks.

I'm not too good either, but here goes...

Side weight meant a lot in the days of rubber and plastic with "pancake" weightblocks.  Side weight means little on newer balls with high tech cores.  Unless you drill a ball very weak (pin on PAP or 6 3/8" away from yout PAP (positive axis point) in your track), the ball will flare ("wobble") as the core rotates trying to get to it's preferred position.  If you come straight up the back of a modern ball (again not drilled super weak), it will still hook.  As Leftside said, it will read the oil pattern earlier.  You will get more of a roll/arc instead of the skid/snap reaction you will get by coming more around the side.

You can use the term "coming up the back" anytime.  It is how you are releasing it, not how oily the lane is, the type of ball you are using, or even how the ball hooks.  If there is a ton of head oil and very dry backends, a reactive ball will skid/snap no matter how you release it.  You will minimize it by coming up the back of the ball, but it's the nature of reactive balls to snap.

The cover of the ball (surface grit and material; reactive/particle) is probably the biggest contributer to how much it hooks.  The pin to PAP distance is next determining the amount of flare.  Next is the position of the CG (center of gravity).  The CG position will fine tune the shape of the hook.  This is a simplication; there are many more details that you may or not care about.
--------------------
Strider
Penn State Proud
Teamwork is a lot of people doing what I say.

Whooahhhhh !
Leftside, Doc & Strider, Thanks for all of your explanations. I see more know !
One more question ? If the game depend of too much factors like that, what is a part of talent, ball technology and lanes preparation in the average of the bowler ?
In the past, when all bowlers owned just one same ball, I think the score is almost imput to the talent of the player, am I right ?
 
ps : I'm not nostalgic, too new in the game !

I agree with InternationalBowler and Brunswick on this one. You can throw any ball drilled any way with any cover stock dead straight. By the same token you can throw any ball and hook the whole lane. It's some degree of axis rotation more than zero that makes a ball hook. I define axis rotation as a rotation of the ball at an angle to its direction of travel. A dynamic core will only "help" the ball hook more if you apply a degree of axis rotation and enough revs to energize it. Some of you that came to the ballreviews gathering saw me throw a V2 pearl straight down the 2 board to pick up the 6-7-10 split. That was done by throwing the ball with near zero axis rotation but with revs and very little tilt. I often will throw the ball this way down the 2 board and pick the 10 pin out of a full rack to show people you can throw any ball straight.
If you need me to explain why I don't think a dynamic core can make a ball hook I will. The same goes for side weight.
That ball flairs a lot when I throw it normally.