5 replies to this topic

[sofla]

How does different lofts on a driver effect back and side spin? For example, does a 9.0 spin more or less than a 10.5 assuming the same shaft and flex is being used and of course the same head and ball. I hope the question is not too vague. I just returned from a demo day and hit the Tour Edge Exotic XLD real well (for me).  There was only a 10.5 in the shaft and felx I liked so hence, this post. Thanks in advance.

[Viewing As Guest]

[rybo]

A 9* will spin less then a 10.5* given the same design and struck in the spot on the face.  

Your backspin/sidespin question is not nearly as clear cut.  A ball can only spin (rotate) in any one direction at a given time.  So any type of sidespin reading is usually a less accurate reading of a combination of face angle and swing path and its potential directional effect on backspin rotation (ie.. fade, draw,etc)  Difficult to explain in a short paragraph.

[Gehly]

BTW, how'd you like the XLD? I have a new 9* coming in stiff, but haven't hit it. I hear the Exotics play pretty true to loft.

Edited by Gehly, 17 February 2008 - 10:55 PM.

[Gehly]

depending on how I hit the 9, I may be willing to trade for a 10.5

[bignose]

rybo is right in that given everything else equal, a lofter loft means less backspin.

While it isn't quite this simple, basically, the amount of sidepsin is wholly a function of the non-squareness of the face of the club at impact.  That is, any club left 2 degrees open will impart the same amount of sidespin.  Now, in full disclosure mode, this isn't quite exactly true, but it is pretty darn close.

Where the loft choice affects how the ball's sidespin changes the ball's flight is that with more backspin, the effect of any given sidespin is lessened.  Specifically, a ball actually doesn't feel the effects of sidepsin and backspin separately -- the ball only feels the effect of spin, it is just a question of what angle the spin rotates on.  

I think if I make a few examples, I'll show my point better:  Consider a ball hit with a short iron (something like an 8 or 9 iron) with 8000 rpm of backspin and 500 rpm of sidespin.  This is equivalent to 8015.6 rpm of spin on an axis tilted at 3.57 degrees off of vertical.  The lift force from the spin works in that direction.  Instead of the lift force pushing on the ball straight up and down, it it pushing mostly up but slightly to the side, too.

Now, compare that with a driver hit with 2500 rpm of backspin and 500 rpm of sidespin.  That is equivalent to 2549 rpm of spin on an axis titled at 11.31 degrees off of vertical.  The lift force is directed more than 3 times as far off of the vertical, even with the same amount of sidespin.  

So, the more loft a club has, the more backspin is generated which reduces the effects of the sidespin in terms of how much the ball will slice or hook.  This is because will more backspin, the spin axis is going to be closer to vertical.

Being the club with the least loft, this effect is the most pronounced in drivers.  If you are plagued with sidespinning shots, going to a higher loft can be the difference between being on the edge of the fairway rough or being in the trees or OOB.

Edited by bignose, 17 February 2008 - 11:12 PM.

[sofla]

Thanks for the responses it really helps because I am between lofts and needed this guidance.

As for the XLD. It was the hit of the demo day, IMO. Everyone was hitting them. There was a long drive competition where you could hit any of the manufacturers drivers and many, if not most, were grabbing the XLD.  I just got the Hibore XLS (after successfully using the XL for a year) but this might kick it out of the bag.

In the interest of full disclosure, the only other companies there with drivers were, TaylorMade, MacGregor, Adams, Nike, Srixon, Mizuno.