Ask The Professor Archives Part 1

I basically understand the 'spring-like effect' or 'coefficient of restitution' (COR). My question is:

Does the non-conforming Callaway ERC II driver reduce the compression on the golf ball and help retain more of the golf ball spherical shape at impact to more efficiently transfer energy to the golf ball thereby allowing the ball to fly farther.

JK: If this answer is known, it will be by someone with very sophisticated equipment and the engineering ability to understand metallurgy, physics, and ball composition. I doubt this technology exist in the golf industry.

Another way to ask... I used to be under the impression that more compression of the golf ball at impact meant more speed. However, the trampoline effect of the ERC II driver minimizes this?

This one I can answer: The COR goes down dramatically with club head speed. The higher the club head speed, the less the COR. This is why the distance of the average Tour player (club head speed around 110 mph) is only 20 yards short of the big hitters (whose club head speed is between 120 and 135 mph).

In "Science And Golf II" by Cochran, an article by Chou, Liang, and Yang of Drexel University and Titleist titled: Contact forces, coefficient of restitution, and spin rate of golf ball impact, provides the specific data.

I agree with you that much golf instruction is contradictory and simply contrary to physics and even simple observation -- they show one thing and describe something else! I've been trying to learn your method and am getting better each time I practice.

My question deals with my observation. In your Kuykendall Toss, you mention how long the backswing is, how you hold a ball to toss it and so on. What isn't mentioned is that you face the target when you toss a ball. In golf, this isn't practical (or maybe illegal). In three sports where an object is hit from the side: hockey, baseball and tennis, at the point of impact, aren't the players hips open, at least slightly?

Maybe my observation is wrong, or maybe they're not hitting optimally, but I would like to hear why facing the ball at impact is the optimal position.

The only function of the body below the shoulders is to stabilize the swing. Any opening of the hips just adds additional motion and maximum torque on the back.

The hips and legs contribute virtually no club head speed. The only connection between the lower body and the upper body is the spine. For any of the speed of the hips and legs to be included into club head speed, the shoulders would have to be aligned with the hips at impact. If they were aligned with Tiger Woods original swing, he would not have been able to put the club face on the ball. His club head would have been 24 inches inside the ball and facing 90 degrees to the left.

Recently, I participated in a golf tournament. I saw a player always used his club to hit the turf about 1 foot in front of the golf ball so as to align himself to the target during addressing. Are you allowed to do so?

NO. Rule 13-2. A player shall not improve the position or lie of his ball by any of the following actions:

* creating irregularities of surfaces.

I'm very poor in putting on the target line. When reading the green behind the ball, I can easily spot an imaginary line toward the target. However once I step over the ball and during addressing, I will lost my imaginary line. Recently I think I saw Kenny Perry (Buick Open) has a straight line drawn on his golf ball. Are you allowed to have a line drawn on the golf ball to aid you in aligning during putting?

Your assistance is greatly appreciated.

Yes. Although I don't remember the exact rule. Check with the USGA for the rule that allows this.

I ordered 4 of your Kuykendall designed clubs. One of them is a 5 iron. I use your LPG system and it works great except for my 5 iron. Nothing wrong with the iron. I hit fat or thin. Is the swing different than for the 7-9 irons.

Is the swing a little flatter for the 5 iron? Your help would be appreciated.

The swing is not different. It must be exactly the same. This is probably why you are experiencing some difficulty. With traditional clubs you must swing the longer clubs faster and harder in order to achieve distance. With the Impact scientifically assembled clubs, you must swing the same.

a) that's just the rule for equipment in tournament play

JK: USGA Rules of Golf. Shaft cannot be more than 5/8" from heel of club.

b) torque around the shaft is minimal during swing (i.e. forearm control)

JK: No. Torque is several degrees during a swing. It takes time to get use to the reponse of a shaft.

c) at impact, time of actual contact is so slight that there is neglible

JK. No. There is major twisting of the club head when not caught on the center of gravity of the head.

time for rotation of the head around the shaft to have effect?

JK: There is 3/4" of travel and 0.0005 second between contact and separation of the ball from the face. There is plenty of time for the ball to twist the head, or for the head to produce ball spin.

I can see why the "Big Bertha" type heads would be disadvantageous (besides air drag) if b) or c) have influence.

I look forward to your comments.

JK: All oversized heads have disadvantages. This is why you only see blade size irons in 99% of the tour players.

There are no rules on the mix of your clubs. You can have any combination of right and left handed clubs you want. You just cannot exceed 14 clubs. You can play with 14 different putters if you want.

Are all the golf clubs having standard length? For example, is my standard 8-iron has the same length as Tiger Woods 8-iron? If not, is there any minimum and maximum allowed length a golf club can have?

There are no standards for golf clubs. There is only a minimum length - 18".

Would I be able to send my clubs to you and have you reshaft and put the impact grips on them and try to put them as close as optimal as you can?

YES. You will need butt extenders and the optimization of adding weight to the shaft. The cost is $25 per club.

If the flexing of the right forearm creates close to 50% of the swing speed how did I achieve 76 MPH

It is combination of flexing and extending that creates the club head speed. I have never said it was just flexing.

I follow your swing and it really helps but it seems to me that Scott's swing and Moe Norman's swing do not involve bending the left arm at 90 degrees. Is this true and, if so, why is that? Which is correct?

The straight left arm started with Bryon Nelson. It was a major setback in the golf swing. Jorgensen has calculated, in his book, "The Physics of Golf" that you can get up to a 50% increase in club head speed if you bend the left arm. It is more on the order of 5% in the real world.

My Lever-Power-Golf system takes my Single-Axis discovery to the next level - makes you more accurate and longer.

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