Wednesday, February 20, 2013

MOI Balance Index – A Lengthy Introduction

Before I start with this post, I would like to announce that I am planning on doing a Top Club Fitter/Club Maker List for 2013. This will come out at the same time my 3Jack Golf Top-50 Swing Instructor and Top-25 Short Game/Putting Instructor Lists will be out. So expect that to come out around July.

The Club Fitter/Club Maker list is open to anybody who does Club Fitting either part-time or full-time anywhere in the world. If you are a club fitter and are interested in making the list, please send me an e-mail at and we can further discuss your experience and credentials. Personally, my goal is to create a top-50 list of club fitters I believe are a step above the rest, but I plan on doing only a Top-25 list this year due to it being the list’s first year in existence.


If you have read the forum lately (, I started a thread called ‘MOI Balance Index.’ I have just discovered MOI Balance Index that some clubmakers are using to fit clubs at the highest level of fitting.

But first, a background into how I got into this…

Back in 2011 I had been reading articles and golfer’s posts on the value of MOI matching. I didn’t quite understand it other than it was supposed to be a replacement for Swingweight Matching.

For a long time, there were many issues I had with swingweight matching, like:

It’s not really a scientific measurement. Scientists do not use ‘swingweight’ in any form of scientific study or measurement.

The swingweight scales seemed very inaccurate and inconsistent. I had taken the same clubs to different clubmakers and come back with noticeably different swingweight readings. The only consistent swingweight machine seems to be the digital swingweight machine.


It did not make much sense that a golfer could replace a 50 gram grip with a 62 gram grip and the swingweight would become lighter.

Having been to the demo day version of the PGA Show where clubs are all marked with the swingweight, they often felt extremely different from a heft perspective despite having the same swingweight.

I ended up putting together a set of Wishon 555 model irons. The 3 and 4-irons were cavity backs, the 5-PW were musclebacks. I ended up liking the set overall, but I noticed that once again, I hit some clubs far better than other clubs. In this set, I hit the 4-iron and 7-iron the best. And I hit the 3-iron and 9-iron the worst. Eventually, I started to understand what MOI matching was about.

It is measuring the MOI of the ENTIRE golf club, not just the clubhead.

This produces a measurement (MOI) that determines the amount of effort to swing the club. The key is to determine how much effort the golfer produces in their swing. Find the match and that is how you find your optimal MOI. From there, you simply match the MOI for the rest of the IRONS (drivers, hybrids and fairway woods are different).

With that, I took the plunge and purchased an MOI machine


When I measured each of my clubs, I found the following.

The worst clubs in my bag, the 3-iron and 9-iron, had the 2 lowest MOI’s of any club in my bag (2,620 and 2,638 respectively)

The 2 best clubs in my bag, the 4-iron and 7-iron, had the 2 highest MOI’s of any of the irons in my bag (2,702 and 2,695 respectively).

This all led to me fitting for my own MOI and I discovered my optimal MOI with the irons is at 2,725. And that is why I hit the 4-iron and 7-iron so well, they were both the closest irons to my optimal MOI of 2,725. I also started to measure the MOI of all of my old sets of irons and found in EVERY set that the best irons I hit were always close to my optimal MOI and the worst irons were far away from my optimal MOI.

Eventually I wanted to fit for MOI with my driver. I used a Wishon 919THI driver for the fitting that I never gamed because the ball would fly too low. As I fitted for the MOI with the driver, not only did the impact dispersion improve, but the ball flight improved dramatically. That’s when I was sold on the concept of MOI matching


One of the things I discovered after MOI matching was that not all MOI matches feel quite the same. Furthermore, while MOI matching greatly reduces the impact dispersion laterally (heel to toe), if your swing is not quite on point you can still miss the sweetspot point either high or low like you can with non-MOI matched clubs.

And while I never experienced it myself or with a customer, I had heard some people complain that either the long irons either felt too ‘head light’ or the long irons felt too ‘head heavy’ in a MOI matched set.

Lastly, I started to notice that not all MOI matched clubs feel the same. I had some Edel wedges that I personally MOI matched. But they felt fairly heavy to me and when I measured the static weight of the clubs, I found them to be very heavy. I then removed the KBS C-Taper shafts and found that the Edel head weights were very heavy, with the 56° wedge weighing in at 307 grams (normal is about 300 grams) and the 60° LW weighing in at 309 grams (normal is about 302-304 grams).

I eventually replaced them with a much lighter shaft (Dynamic Gold SL) and a lighter grip (50 gram Iomic Sticky 2.3) and started hitting the Edel wedges superbly. In fact, the 60° LW is the best lob wedge I’ve ever hit.

This is where I started to notice the importance of STATIC WEIGHTS and the importance of weight in the 3 major components of each club (grip, shaft (trimmed) and clubhead). I started to try this with a few customers and started to see a difference in being able to MOI match clubs versus MOI matching clubs and finding the optimal combination of component weights. I found that I probably play best with a 50 gram grip, 105-118 gram shaft and more weight in the clubhead. I also found a customer with the same optimal irons MOI and he played better with more weight in the shaft and grip and less weight in the clubhead.


This leads to MOI Balance Index (MBI).

Recently, I had mentioned what I had discovered with MOI matching and understanding the weights of the main components. And this is something that has been worked upon by different club fitters. In fact, one of them spent 3 years perfecting a ‘calculator’ to determine MBI. It can be found here:

So, what is MOI Balance Index?

First, you need to MOI fit and match your clubs. When you do this, you will notice a great improvement in how precise the impact contact will be. However, you will still find some clubs that you noticeably hit better than others.

The club that you hit best is the club that you want to find where the balance index of the club resides. Some clubs the balance index may be more towards the butt end of the club. Other clubs it may be more towards the clubhead. If you can find the MBI for that best club that you have already MOI matched, you can then match determine the MBI for the rest of the clubs and then work to match them to the best club.


As it shows in the spreadsheet, it is a time consuming process. And according to the spreadsheet creator, it may not be feasible if you are running a business.

But, I have found some very interesting things with the spreadsheet.

EVERYTHING matters. Head weight, shaft weight, tip weight, grip weight, grip cap size, ferrule, lead tape, etc. Everything plays a factor in your MBI calculation.

The type of clubhead matters. Driver heads will alter the MBI from a fairway wood head. Same with hybrids and irons.

The type of iron heads matter in MBI. A game improvement style of iron will alter the MBI than a muscleback which will alter from a regular cavity back iron. And if you have every hit the same club but going from a GI head to a blade head, you can feel a different balance.

And that is in part of what MBI is really about. While MOI matching figures out the amount of effort involved in swinging the club, the MBI gives more of a determination of feel and helps produce the same feel for all of the clubs in the bag.

I plan on doing MBI with my next set of irons, which will be a set of the Wishon 575MMC irons


I’m currently working on a few new things with my swing after my latest lesson with my instructor, George Hunt ( After that I would like to try out the new PURE grip model (PTX) which should come out in April. At about that time I will probably purchase the irons and I will update my progress working on MBI.


1 comment:

Unknown said...

Did you ever build that set of 575 wishons?