MyGolfSpy Labs: Shaft Flex Shocker! – {Are you playing the wrong flex?}

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Are You Playing The Wrong Flex?

Read this before you get fit!

Why? First of all the majority of golfers still have never been fit for a single club in their bags...and for those that have we estimate that over 50% of you still are not playing the correct shaft flex.  And if you include further fine tuning (which you should) to the in between flexes...well over 80% of golfers are not fit with the right flex.  Whether you go to a high end fitter or your local big box, one of the most important decisions you will ever make about your new clubs is picking the proper shaft flex.  Want to make sure you pick the right one?  Read this shocking data in our latest "MyGolfSpy Labs" series.

MGS Labs: Shaft Flex

What do you know about shaft flex?

I'd guess that most of you would have heard some of the following bits of "common knowledge" and or myths regarding shaft flex:

  • I hit the ball ____ far therefore I should play a stiff flex.
  • faster swing speeds equal stiffer shafts
  • slower swing speeds equal weaker shafts
  • A softer flex gives you more "kick" and ballspeed
  • A stronger flex makes the ball fly straighter
  • whippy shafts make you slice the ball
  • You should play the softest shaft you can control OR You should play the stiffest shaft you can get airborne
  • Stiffer shafts are "anti-left" and softer shafts are "hook machines"

Well, friends, you can trust that where there is  "common knowledge," you can find me close behind to either validate the "wisdom" with data or burn it to the ground.  Today I'm taking on the topic of shaft flex. A highly under-rated aspect of the fitting process.

Shaft flex is probably the most common component of club fitting.  Even those golfers who eschew the benefits of a more complete fitting usually want the right flex in their shaft.  But what is the right flex?  How do you find it?  What are the benefits?  And what are the problems with playing the wrong flex?  We're here to help you find those answers.

MGS Labs: Shaft Flex


For this test, we had three golfers test drivers with regular, stiff, and extra stiff shafts.  Every player used the exact same head: a 10.5* Callaway RAZR Fit.  To keep the testers from knowing what shaft they were testing, UST Mamiya supplied blacked out shafts with no distinguishing marks (I marked the grips so that I would know which shaft was which). The shafts were the same weight, torque, and bend profile, the only difference was flex.

Each golfer hit 10 shots with each shaft and the results were measured by our FlightScope X2 launch monitor.  All testing was done at the range at The Bridges of Poplar Creek Country Club.

MGS Labs: Shaft Flex


The results of our test group spit directly in the face of conventional wisdom: THERE WAS NOT ONE CONSISTENT TREND.  Even the shaft manufacturers, give you guidelines such as "Stiff flex fits 90-100 MPH," clubhead speed is only a starting point If we had fit our testers only based on clubhead speed, our highest swingspeed player would have lost 9 MPH of ball speed!

Now, before you run to the comment section and say that three testers is not a big enough sample size, please read the next paragraph:

As I compiled these results, I was shocked by what I saw.  I immediately fired off an email to UST Mamiya to see if their findings (they have done this same exact test with hundreds of golfers) were equally chaotic.  They assured me that they were.  Sometimes a slower swinger needs an X-flex.  Sometimes a big hitter needs a mere stiff.  It's all about fitting the individual and there are no hard and fast rules.

MGS Labs: Shaft Flex


So, how did our "common knowledge" hold up?

  • A softer flex did not equate to more ballspeed
  • A stronger flex did not universally create straighter shots
  • For 2/3 testers, the stiffer shafts did minimize the amount of "left" in their shots.

So, if we're generous, "common knowledge" went 1 for 3.  Not bad if we're playing baseball, but not very good when we're talking about a new club purchase that can easily eclipse $300.

There are two things you should keep in mind when buying your next driver (or any club):

1) Shaft flex is a very important variable in fitting.  Our testers saw variations of as much as 22 yards of distance from one flex to another. Getting the right flex is key to an optimal fit.

2) "Fitting" by guesswork and common knowledge does not work.  Period.  You need to get fit by a trained professional.  Let me go a step further: you need to hit the exact combination you're thinking of buying because you never know what it will do until you hit it.  Keep our big hitter in mind: with his 110+ MPH swing, "common sense" would have given him the X a cost of 9 MPH of ball speed and 22 yards.

(MYGOLFSPY LABS) Powered By: FlightScope X2


{ 111 comments… read them below or add one }

Bigleftygolfer May 9, 2016 at 1:09 pm

Great article and my game is an epitome of this article all wrapped up into one! I am a scratch golfer and I stand at 6’6″ tall with a smoooth swing that people never believe my club head speed is really 118mph! Again I am tall so for me I have tour x MSI 125 in my woods then I have kuro kage 80 x stiff in my hybrid 2 iron now here is the fun part I have regular soft tipped ctaper silver satins in my mura blades albeit they are all bent flat to varying levels -1 to -4 and my wedges I use senior shafts! Also bent flat -1 and standard on the 60!

Of course this was all mapped out by a very good club fitter over many hours of sessions so listen to the article get fit by a real fitter with real experience as my body an ss numbers would say I need all xx stuff but that is only true for me with my woods and hybrid (anti-hook setup) however with every other club I use weak shafts and they perform great also my 6 iron carry distance is 183.7 as a point of reference.

So remember shaft plus bending tweaking makes all the difference. I could use all xx stuff and bend my irons up however that scenario had me losing about 15% of distance and I lost some accuracy.


todd August 18, 2016 at 11:29 pm

You are 6 ‘6″” n you have your irons bent to 2 degree flat every person that i know that aroud my height uses irons that are bent upright


sean ryan October 20, 2016 at 9:05 pm

Not always. That assumes you are playing “standard length” shafts. if you are playing longer than standard shafts you may well need to play them flat.


Megan April 21, 2016 at 11:06 pm

I was wondering if there was any way I could get the name of the author of this article and when this was published? I just did an experiment about this myself and I was hoping I could cite you in my report.


Phil Christie March 25, 2016 at 9:27 pm

Hi. Just bought a set of ping i25 irons. I tried and tried to get properly fitted with proper iron shafts. I Did the club compare at Golftown. I had Mizuno fitter check swing speed to 89 miles per hour. It said dynamic gold x100 shafts. Went to return clubs as I thought they were too stiff. Tried against cfs ping stiff shafts . The x100s reduced the height and get better penetration and lower ball flight for me . I believe it is determined more by your tempo than your swing speed.I believe you need to go by your own feel and your desired trajectory.


bob jones November 26, 2015 at 9:16 am

I forgot to mention torque and kick points and surely a shorter person requires longer clubs to increase the swing arc as well….thus producing longer shots?


bob jones November 26, 2015 at 9:12 am

people go on about shaft flex etc but no-one ever mentions the weight of the shaft…surely the lighter the shaft in accordance with your swing speed the faster the club head speed and wouldn’t this apply to every club in your bag? so for example wouldnt a 90mph smooth golf swing be better off using 65g graphite shafts for their woods and hybrids and 90g shafts for their irons? then you have the choice of rifle or stepped shafts for irons as well..????


Andres October 23, 2015 at 4:34 pm

3 of 4 people found the flowoling review helpful the clubs i was looking for, July 31, 2011Bya0 Amazon Verified Purchase() This review is from: was looking for a set of hybrids and this really fit the bill nice thick grips fit my hands great and i like the bright head coversHelp other customers find the most helpful reviewsa0Was this review helpful to you?a0 | a0


Steve September 14, 2015 at 10:23 am

I am hitting a titleist 915d3 8.5 with diamana whiteboard 70 stiff, I need a little more draw…is the new 3rd generation d+ 60 ct regular flex a good idea or is ther a cheaper version of something else to keep the ball down? Hdcp 6. Age 53, driver speed 102 smooth tempo


Ken Kaminski August 2, 2015 at 11:33 am

Great website.


baudi February 24, 2015 at 5:54 pm

Without Launch Angle, total Height and Angle of descent it is tough to deal with these numbers The efficiency of the trajectory leaves many questions.


baudi February 24, 2015 at 5:48 pm

The data show the following numbers :
1- 151 mph ballspeed equals 259 yds distance
3- 158.8 mph ballspeed equals 262 yds distance.
The difference in measured spin is only 100rpms

Nearly 7 mph more ball speed and only 3 yds difference…
These are the kind of results that secondary analysis becomes a risky business.
However, I am having a hard time to believe that the distance gap is so small.


John Dee January 19, 2015 at 11:13 pm

Personal experience..
I had purchased a Titleist/Cleveland/Callaway driver off the rack over some 2 years but was unsatisfied with the results
Went to the most respected golf pro/fitter in country for a driver fitting.
He used a trackman and searched for a shaft/head combo that produced the “optimum” launch angle.
Went through around 10 heads and perhaps 12 shafts….I wasn’t counting because I was relying on his expertise to find the result I wanted
I was shocked at the cost but figured I could justify it given the expected/promised outcome.
I also succumbed to the sales pitch that results cannot be achieved in a 1 hour session but that I now had the equipment that …with lots of practice…would allow me to reach my goals.
I sold the club some 3 months later for 31% of the purchase price.
Yeah…31.6% actually…it still bugs me.
I then went to a US site online and bought over a period of time 4 drivers covering a range of specs…used /unmarked condition…and played at least 4 times a week for months.
Sold all 4 drivers on eBay
From that I bought a new driver…that I knew was for me.
Moral: Carpetbaggers are everywhere and their main …sometimes only…focus is your wallet.
The idea that you can go to a demo day or an in-store club fitting and “get fitted” in maybe
an hour and 20 balls later is absurd.
Demo days are great though…you get to hit lots of clubs of different specs , but this is
only the start of a long, long process.
Oh btw…get a GPS or Rangefinder and record your actual stats.
Some of these 60-70+ year old amateur golfers on this site are hitting 300+ eh?
Yeah, right.
In 2014 Nicklaus, Player,Palmer hit off the 1st Tee at Augusta…a ceremonial hit-off to mark the beginning of the 78th Masters.
They hit 228 / 227 / 184 yards respectively as measured with a Bushnell Hybrid Rangefinder.


Andy January 15, 2015 at 9:55 pm

I’ve always distrusted clubfitters and so called equipment experts because of this. I never heard Hogan talk about clubfitters. After 40 years of expensive experimentation I trust myself, not a club fitter, to get it right. I’ve been laughed at for using x-stiff wood and hybrid shafts for years with a 92 mph swing speed. I’m shorter and crooked with the recommended regular or stiff shafted drivers and woods. Why? I have an efficient, no b.s., smooth swing that is grooved, accurate and efficient with the driver and 3 wood. Supposedly, according to a number of club fitters I shouldn’t even be able to carry the ball as far as I do with my swing speed… I carry it 225 at 92 mph… and do it all day long. I found out myself I need to know where the club is, and want to know where it is when swinging full out… it can’t be flailing around out there. It took me 35 years to figure out lightweight x-stiff wood shafts work best… not in the irons, though, unless they are lightweight graphite–they need to be stiff. I’m liking 95 NS pros in the irons.


John June 27, 2014 at 3:49 pm

Hi, Can anyone tell me how good the shaft in the Nike VRS Covert, Dynalite 90’s are, apparently that’s the standard shaft that comes with the irons. I’ve been playing MizunoMP53 KBS stiff, which feel fantastic, however I’m, stepping down to a regular shaft and was wondering had anyone used the True Temper Dynalite 90. also any comments on the irons would be good too.


John Malihi June 27, 2014 at 1:10 am

Hi I’m in a bit of a dilemma with flex. I have a driver club head speed of 97 to 102mph, my irons are from 88 to 95mph I hit my 6iron 158yds. I am currently using a KBS tour stiff shaft. I had a hit withy friends 9 iron in tegular and it felt good almost effortless. What do you think please.


David June 27, 2014 at 9:38 am

This is solely from my own experience…….

My swing speed with a driver is about the same as yours and I average in the 230-240 range. No problem here and stiff flex fits the bill.

Don’t recall my iron swing speed but was using stiff flex Pro950GH soft-stepped once. But I had no consistency except in the fact I wasn’t hitting greens. So I changed to regular flex Pro950GH HT, hard-stepped once. In addition, I slowed my swing down and concentrated on a smooth swing and making good contact. The HTs have a nice high trajectory (duh, that’s what the HT stands for). And get thus, not only is my accuracy going up, but my yardage is increasing slightly. Since making the change I have broke 80 for the first time. No flukes, because since breaking 80, I have scored in the 70s 5 of the 7 times I have played.

So for what it is worth, if you hit your friends club and liked the results, I’d say give them a try. My system of getting the ball going with a stiff driver and then slowing down my swing in order hit greens seems to be working for me.


Dennis June 25, 2014 at 3:28 pm

I liked the article, but don’t necessarily agree. I think for most golfers, practice is more important than anything else. I’ve always played clubs off the rack. I’m 67, 5’11, 190 lbs. with a SS of about 90. I play stiff in both my woods and irons, I don’t change clubs very often. I’m currently playing a Callaway Great Big Bertha II (380cc) 7.5* driver that I hit about 240-245, and ping i5’s, and hit my 7 iron about 145-150. I concentrate on accuracy and forget about distance, because I don’t think equipment is going to change things significantly enough to buy something new. By the way my handicap fluctuates between 0-2 most of the year, it goes up a little in winter, because I can’t swing very well in a coat. I don’t try to work the ball either way, I just hit it straight. My point is, spend your money on lessons or hitting practice balls, not on equipment, especially shafts, unless you’re going to be making your living playing golf. Shaft selection is so technical you’ll drive yourself crazy (and broke) trying to find the right combination. When I was a kid I couldn’t afford to play golf, but I had a neighbor who worked as a club pro on an Air Force Base, and when clubs were turned in to the lost and found and not claimed he would bring them home to me. In my freshman year of high school none of the 12 clubs in my bag matched, but I shot in the high 70’s most of the time. There’s no magic wands, you have to set up correctly, align your self correctly and hit your target. Forget all the marketing and hype, and you’ll beat the guys that have new sticks every week. Just my 2 cents.


J.T. Parker February 22, 2016 at 7:11 pm

I am similar to you in everything you said. I have never worried about distance with irons. I could swing hard and hit further but be inconsistent like those I play with who like to announce how far they just hit their 9 iron. The one thing though is I believe you are missing something by not updating the driver. I stayed with an older Callaway Octane but fondly tried a Ping G30. More forgiving and just as long. Easier to swing as well.


Stiles May 4, 2014 at 3:26 pm

After reading all through this article and the comments I think I will try a few different drivers with a variety of flex and then spend all the rest of my energy on establishing consistency in my short game and ease in my swing instead of finding the next innovation which will “make me play better”. I have seen guys on the “rural” course I play on who have played, as a pastime, for years with 25 year old, beat up garage-sale clubs or hand-me-downs. Some of these guys who cannot afford all the latest technology and gear, and play maybe 2 to 3 times per week, range from single digit HC’s to low/mid teens.


Squonk April 26, 2014 at 8:57 am

This is all interesting and I would gladly get fit, but living in Japan there is a language barrier. And even forgetting about communicating with the fitter, which I could handle, it’s finding a reliable fitter that poses a problem. I’ve actually considered a trip back to the States for a fitting, but that little scenario has already been described in this thread and it didn’t turn out so well.


Ben April 25, 2014 at 1:48 pm

It is a good article. I agree with the article and have experienced it myself. In every experience with a club fitter, they all pointed me to Stiff flexes because of my swing speed and discouraged going to X-flexes. However, I have tried many X-flexes and liked the way they release through the ball better for me. So, I switched to X-flex and dispersion was better and ball speed was better.

I think a lot depends on when a player releases the shaft and finding the shaft that releases through the ball the best. If the shaft releases early there is no whip through the ball and greatly slows the clubhead at impact. There are so many variables to shaft fitting and so many different shafts so trying them gets the best gauge on what works.

I do think further testing and bigger sample size with different shafts. The article only isolates the shaft flex in study which is good. Torque, kickpoint, and weight also come into factor for dispersion and distance. Those factors are another ball of wax. So, I would like a big study done on isolation of torque, kickpoint, and weight also.


Andy January 15, 2015 at 10:07 pm

I totally The agree, and there is also carry versus rollout, which is extremely important depending on turf conditions and fairway width. These static figures of people giving me total distance on their drives is meaningless unless they tell me more. I live near sea level, in Florida, on a very wet course. I use an x stiff driver and 3 wood, with a swing speed of 92, I carry them respectively on average 220-228 and 205-210. Some guy in Arizona might have the same swing speed, hit wide dispersions and occasionally roll them out to 250… From what I have read far too many people are making money selling this or that–ideas, science, or equipment. But the truth is in the dirt. And it is in your own courageous and expensive experimentation over many years. One company says you hit their low compression ball farther because it spins less, the same company and another one, claim you hit the low compression ball further because it spins more. Even though I am a short hitter, I prefer to play the game in the air.


Dan November 3, 2015 at 4:26 pm

Totally agree. Bend profile is key. I always played stiff from an early age (DG S300), had a bit of a break from golf (life got in the way!) and am back playing. Went with a lighter shaft initially to get back in to it (NS Pro 950 stiff). Now that I am back in the groove I’m on to the (NS Pro 1150’s). These are still lighter than the S300’s but play similar in bend profile. I always struggled though to not slice the driver & 3 wood with stiff shafts in, so one day tried an extra-stiff. It was a revelation. So natural. I do not have to consciously ‘time the release’ any more. I can release the club really late too and get a nice crisp ‘snap’ at the ball. This has now affected my iron shaft play and I have realised that I may need an even stiffer tip in those. Trouble is the weight…?


Richard Lucero April 11, 2014 at 9:32 am

One other thing. These experts have the language but don’t get fooled by them.


Richard Lucero April 11, 2014 at 9:22 am

First, most stores don’t fit anyone but there pockets. Secondly , their knowledge of fitting anyone with the right shaft is foreign to them. Find someone that knows something about fitting clubs. Do research and don’t depend on so called pga pros.


Jeff Fones March 25, 2014 at 5:55 pm

I have tried TOO many iron sets and fell prey, with my 85mph swing speed and age, 70, to the general admonishment that I needed Senior graphite. Then recently while trying yet another set of irons, I was handed a set of Callaway Razr X in Uniflex. They went straight, and on the course they still went straight and felt great.


David April 17, 2015 at 1:15 pm

The Callaway Uniflex (I assume it to be Nippon) is Senior flex! I’ve measured them.


Tom Miller March 12, 2014 at 10:01 am

I find this very interesting and would love to find a qualified club fitter. Unfortunately I haven’t been able to find any in my area (upstate NY).


Tedd-0 January 15, 2014 at 9:44 pm

Dear fellow golfers. I am a very high handicapper type of player. I just regripped all my Iron clubs on regular graphite shafts. I had been hitting in the high 90’s. Average 97. After the regripping of my clubs I suddenly shot an 88. I was so extatic that I thought I would go ahead and complicate things by purchasing new STIFF graphite shafts. All came in except one. I reshafted them myself except for my 4 iron. I put the same grips on from my other set that I shot a 88 with. My last shaft came in so I installed the 4 same way. Well, they go real high now! Man they feel very nice except for the 4 iron. The 4 iron is a DUD.. It hurts my hands when I miss hit it. It doesn’t even feel like the others at all. Distance used to be 180 and now at best is as far as my 6 iron 150 when hit well. What and why is this like that? Do I need regular and not stiff for the 4i? This seems like it is going to cost me to get it right. Any help is genuinely welcome.


David April 17, 2015 at 1:25 pm

The new shaft is either the wrong flex or it’s misaligned. Pull it and have it spined. I did this with my wife’s Callaway Gems. They all clanked. After aligning the bend point to the target, all the irons hit wonderfully with a sweet feel at impact. I’ve played them myself many times. Interesting that I hit these very flexible shafts normal distances(7i-150yds).


purelogic May 3, 2016 at 11:02 am

I wanted to give you some advice, but thought better of it. Instead I will tell you what I would do. Take your 4 iron and wrap it in fish wrap and throw it in the garbage. My 180 yd. club is a
Ping low profile 5 wood. With a smooth 6 iron type swing you will hit that 5 wood 180 (your distance may very) all day. Believe me once you get your yardage dialed in you won’t be concerned about the 200 yds. into the green. I even bought a 33 degree (13) wood from Thomas golf ( love that company), but wanted to send it back because it didn’t go very far. Thomas’s reply was keep it, you’ll grow into it!!! The SOB is right, of that I am sure!!! So it sits in a place of reverence until the day I “grow into it”. Used woods are a dime a dozen and with your experience building clubs you can experiment all you want. You don’t need conventional wisdom. Just as a for instance I made up a 20yo 13# Cleveland Launcher 3 wood mated it to a driver length Diamana flower band shaft. With a good turn that thing is a monster (maybe 240 yds.). All you folks that are laughing lets keep things in context. To a 147lb., 71yo. senior a 240 yd 3 wood is a MONSTER you can believe me. Cheers
yeah…… I know this thread is over a year old, I just felt like talking……………..


W. Scott January 5, 2014 at 11:19 am

The article really rings true. But don’t most professional “fittings” cost a significant amount? With the new monitors, can a player rely on Dick’s or someone like that to fit him for the best shaft? And why don’t the big companies have many, many more fitting days ans sites available around the country? I live in a rural area and they never seem close to my location.

One more thing, why don’t the big shaft manufactures have fitting days? It seems like a shaft that fit you would work fairly well on whatever set of top line clubs you might play and it would be worth changing out all your shafts to get the right ones in all of your clubs.


Nick September 17, 2013 at 11:17 am

At a GolfSmith launch monitor I was hitting an extra stiff fujikara about 20 yards longer than a stiff and regular shaft, my clubhead speed is barely 100, go figure. With the extra stiff you can actually feel the ball compressing.


Trevor September 6, 2013 at 8:49 am

Great info.
Just wondering how you get a difference of 22 yds for the big hitter. I can see a max of 18 of 12 but I’m Not sure how you get 22.

Also, how is one to know for sure that the fitter is legit?



The Club Nut November 9, 2015 at 8:26 am

In my experience, good fitters will talk with you and not at you. Too many box store fitters will have you hit 2 clubs and tell you what you want. A good fitter will earnestly ask you what you’re looking for and will ask you about your whole game and style of play. They’ll ask you about your grip, equipment wear, and fitness. Most of them won’t try to sell you anything, they’ll just recommend something. Also, they will most likely have you come in for a follow-up appointment for any tweaks that need to be done.

That’s been my experience,and that’s what i patterned my business model after. A legit fitter will fit your game, as opposed to someone that has too many of one brand on the shelf.


OldGuyGolfer August 4, 2013 at 7:30 pm

This study is a good start but it is incomplete. The data needs to be correlated to the exact club face location that impacted the ball. Just a little variance from the center of the sweet spot results in significant loss of distance. There are 8 off center locations. 3 across the top, 3 across the bottom and 1 on each side of the sweet spot. To be accurate the study needs to include this date.



DC July 9, 2013 at 2:17 pm

I have an old set of irons that I think has the right flex for my game. I’m looking to pick up a new set of irons. Is there any way to determine the flex stiffness and kick point of the existing shafts and then be able to compare that to new clubs in order to find something comparable?



Pat June 27, 2013 at 9:15 am

I am glad I read this thread. I borrowed a driver playing a scramble. It was an 8.5 Adult shaft.
I am playing a 10.5 regular(was fitted). Conventional wisdom would say that no way this club would work. Holy cow did it ever. No kidding, I got 25 to 30 more yards. That really confused the heck out of me.


Todd April 1, 2013 at 6:42 pm

Good job, guys. Scientific research has shown that the difference in clubhead delivery and resulting ball flight within a wide range of shaft flexes is very small. Not at all what people THINK it would be. The differences in your test, which don’t follow what is known, are due to the differences from swing to swing, most notably the impact point on the clubface.


Eric Small February 28, 2013 at 7:44 pm

I read your write up last weekend and decided to use the info when I went in to get fit for a new big stick today. Just a little about me, I am a 15 handicap who has been playing for a little over a year. I have a 90-95mph average swing speed on my driver and usually only hit my drives 200-220 as I have a lot (+4000) RPM of backspin. I have been fit multiple times and have only once been fit with a S Flex shaft as every other fitting has resulted in an R fitting.

Fast forward to today and I go in for my fitting not expecting anything out of the ordinary. I bring in my 910D2 for comparison to whatever the fitter throws at me out of this years new offerings. I don’t really want to buy anything, but everything this year is being touted as low spin and I definitely need that down. We start off with R11’s, Covert’s, 913’s… R flex, S flex, and nothing is changing. Just the same old thing. 20 degree launch angles, 4500 RPM of back spin and about 220 yards… my own personal hell i’ve been trapped in since I took this game up. I’m getting ready to call it a day when I think of your article and ask to try an X Flex. The fitter almost laughed in my face pointing out my 96 mph swing speed was nowhere near enough to support that stout of a shaft. I insisted though and he asked if I wanted to try the new Cleveland Custom XL’s that they got in today. He said the only problem was that the X Flex they got had a 7.5 degree head. I told him I’d give it a shot since my launch angle was way to high anyways.

What ensued was 15 minutes of ball striking that left both of us with our mouths open. With the same swing speed (96mph) I was hitting an X Flex 7.5 between 245-255 with launch angles around 15 degrees. My backspin average went from a 4700rpm average to 2400rpm with almost no side spin. I had increased my distances 20-25 yards while increasing my accuracy 9 yards from center. The fitter was literally shocked saying that nothing would have ever made him hand me an X Flex unless I had asked him for it and that it would totally change the way he looked at fittings from now on.

Thanks for the great write up!


GolfSpy Matt March 1, 2013 at 7:36 am


Thank you so much for sharing your story. This is exactly why we do what we do. I’m very happy to hear that you’re hitting it longer and straighter.




metrybill April 15, 2013 at 4:44 pm

In the old days (my days) we used to think that on a solid and reprsentative swing, a shaft (steel) that was too stiff (flex and torque) would send the ball high left and low right. Similarly, a too weak shaft (again,flex and torque) would send the ball high right and low left. Is that stil considred a norm, al\beit not an absolute?

If there is a clubfitter on this website, can shaft flex and torque affect fats and thins on full shots? b/c the shafr and clubhead flexeforward and toe down before, during and after impact, could a stiffer shaft help fats and a weaker shaft help thins?


Steve December 27, 2012 at 2:36 pm

We need not fret though as Hireko Golf has what they call DSFI (Dynamic Shaft Fitting Index). It’s the only resource I know of that accounts for the disparity in shaft companies shaft flex ratings into account. Check it out guys & let me know if I’m maybe on to something.


Steve December 27, 2012 at 2:22 pm

Great work guys! But your readers may also benefit by knowing 2 more important (I think through my research) factors regarding shaft flex. 1) that there is no industry standard for shaft flex so the companies can call virtually ANY CPM reading on their frequency analyzer whatever flex they want. Meaning that what one company calls “stiff flex” would only be a “regular flex” by another company even though the two shafts have identical CPM readings and this happens ALL the time.
2) That they should also use Pured™ shafts to insure identical orientation. You guys agree?


Golfspy Matt December 31, 2012 at 7:21 am


Thanks for the comment. We’ve discussed the lack of industry standards before. Sadly, whether it’s CPMs or iron lofts, railing for standards is just more tilting at windmills.

As for PUREing, I don’t know. I’ve never seen any compelling independent research showing its validity. It certainly seems valuable, but seems can mean nothing.




Andy September 24, 2012 at 11:07 am

After being going through the fitting process at a prominent Chicago club fitter, and being told that the driver that best fit my swing would cost $839, I did some research on-line and found the guys at Lotus golf in Columbus, OH. They use a device called the FitChip which measures the timing of how the shaft loads and unloads during the swing. Even though I maxed out at 95 MPH, their analysis showed that I needed a shaft that measured 295 CPM, which is off the charts stiff. Since installing their shaft in my TaylorMade R9, I have never hit the ball longer or straighter. Conventional wisdom would NEVER put someone with my swing speed in such a stiff shaft, but all I can say is that it works. It also explains the results that were obtained during these tests quite nicely, FWIW.


Josh September 20, 2012 at 10:59 pm

Very good too know I am glad I read this before I spent that kind of money on an extra stiff shafted driver.


Will Par September 1, 2012 at 8:02 pm

I’m just coming back to read this topic again. My swing speed is in the mid 90’s and I normally play stiff. My handicap is 3 so I strike the ball solid. I’m also older and probably losing swing speed so sometimes I wonder when I’ll need to drop back to a regular flex. At a demo last year, I told the Mizuno rep my swing speed and handicap and he put a shaft in the iron and handed it to me. As I went to hit a few balls, I saw that he had given me a DynaLite XP shaft with x100 flex. I knew that was probably a mistake, but I hit it anyway and really liked the shaft and the way it hit. I later tested the same iron in S300, but I’ve been puzzled ever since as to why I liked the X100 better. After reading this, I suspect I liked it because it reduced my tendency to hook. (I hit the sweetest little draw with the X100.)

But this raises another question. Since we are all so conditioned to believe we should be fit by swing speed, how do we accept (and purchase) a club or set of clubs with a shaft flex that is clearly not a standard fit. In my case, why would a 65 year old guy who can only expect to lose swing speed, purchase x100 irons even if I hit them better when I demo them? Wouldn’t it be just as easy to argue that I should consider R200 shafts?

At the demo after hitting both shafts, I asked the rep why I liked the X100 better. He just said, “You’re a 3 handicap, you’re going to hit any shaft well.” That made me feel good, but it didn’t do anything to help me choose the best shaft. I’m still puzzled about what flex shaft would work best for me in a set of irons. Having written all this makes me want to go out and put X100’s in my irons just to find out.


jmiller065 August 30, 2012 at 12:57 pm

T, since I can’t go any deeper in nested replies… Assuming that the shafts are UST ProForce VTS Silver Blacked out… I have ruled out that 55g and the 85g, 95g because they don’t offer all the flexes in those weights…

The 65, 75 all have slightly different specs to them… The torque is a 4.0 in the Silver on the 65, 3.5 on the 75… where I would call that medium it is a pretty big jump in a 0.5* of torque in the two models… The tip ratings increase on both lines the same as flex increases…

I am not trying to say the numbers were collected wrong more that it is interesting that the X-Stiff had more spin for some players then the Stiff or Regular… Make me question the design of the shaft more then the numbers provided is all…

I just wanted to clear that up is all… You are correct this isn’t for the person that cares about shooting lower scores and maximizing their performance… It is for the hack that doesn’t care about anything and just wants to drink beer :)


jmiller065 September 4, 2012 at 1:02 pm

The interesting thing is that the target audience is weekend hackers when we are on a golf site the reviews equipment and a golf forum that normally only avid golfers would frequent looking for answers to questions and to learn more about the game and equipment available. How many times around here have we harped on getting fit, why on earth would the target audience ever be the uneducated and then to not educate them on something like shaft fitting is almost a crime.

Whatever, If someone that is reading this still thinks “Regular”, “Stiff”, “Extra Stiff” are remotely the same between companies and even the same shaft company in the same model in the same flex label can be drastically different. Just look at number 3 from one of the best known builders –>

For all I know reading this “Lab” is that the “Reg”, “Stiff”, “X-Stiff” all CPM to about the same frequency. The tips section is too weak on all the shafts regardless of label from the spin numbers, with no launch angle numbers and side spin no way to really get an idea of what the profile actually is without looking up the brand of shaft, since they are blacked out and really no exact model given until I started prying around in my comments.

In short the better question is “Are you blinded by shaft flex labels and playing the wrong profile”. I can give you a Regular flex shaft with a supper stiff tip that will preform well in a higher swing speed. I can give you a X-Stiff shaft with a weak tip designed to get the ball in the air and a higher swing speed will balloon the shot and struggle. That was the point that slimjim was making and it is a VALID point.

You don’t know a damn thing about a shaft if you look at nothing but flex code and take the OEMs word for it, like trying to find a needle in a hay stack for a shaft that actually fits you.


slimjim August 30, 2012 at 10:04 am

The numbers that are “way off” are the spin rates. Anyone swinging in the 110 mph range with spin rates in the mid 3000’s is hitting baloons. Did you check the CPM’s of the shafts to see that they were the flex they said they were? When I do a fitting, I make it a point to explain the differences in how the overall profile of a shaft affects the ball flight. Matching club speed, ball speed, launch angle, and tempo, I can build an efficient club that will maximize the persons ability. I don’t look at my clients as unable to comprehend simple physics.


Randy December 25, 2012 at 2:52 pm

Good afternoon and Merry Christmas!

Taking a break from the family Christmas festivities and started to read an article on Shaft Flex in MyGolfSpy. I’ve noticed a lot of different opinions and views and would appreciate yours…if you would be so incline.

I’m looking for a shaft in my driver and have been for the past 6 months. I have also been to different retailers like the PGA Superstore, Golfsmith etc. I’ve tried several new drivers like TaylorMade R11s, RBZ, Ping G20 & Titleist 910 D3…etc. I’ve been on the launch monitors at these retail stores and have still not been able to find a shaft I feel is the correct fit for me as they keep placing me in “stock” shafts. With this being said, here are some hard numbers and facts about my game, swing and myself as a male golfer.

* I’m 5′ 7″
* Age 58
* 160 lbs
* Above average flexibility/good health
* Current Index 8.6 (Best Index 3.2 when I attended San Diego Golf Academy in early 2001/2002)
* Current irons – Titleist Forged 735CM’s with 5.3 Flighted Rifle Shafts (5.0 shafts with extra tipping to increase stiffness slightly)
* Irons – “Carry Distance” #6 160 – 165; #5 170 – 175; #4 180 – 185 yds.
**Here’s where it gets interesting!!**
Current Driver: 10.5 * TaylorMade r7 Quad with Innovative Technology Regular Shaft 3.5* Torg. (Current Shaft) 45″. I have also used these shafts in the same clubhead: Fujikura 26.3 Tour Platform, Grafaloy Prolight with 3.5* Torq. & Graphite Design YS – 5. All in Regular Flex.
* Special note: ALL shafts have resulted in pretty much the same numbers…as follows:

* Launch Angle @ 16 – 18*
* Spin rate @ 3,600 – 4,100
* Clubhead Speed 94 – 95 MPH
* Carry Distance 200 – 205 yds. (Ouch!) **P.S. I use a 19* TaylorMade Rescue Club with a 5.5 Steel Rifle Flighted Shaft I hit 190 – 195 yds!**
* Tempo & Transition: Smooth

Well…that’s my story! Any information/suggestions you can or will provide as it would relate to a driver/shaft I would greatly appreciate!

With warm regards, a frustrated golf from Arizona!



slimjim August 25, 2012 at 7:47 am

While this test is a step in the right direction, I feel it is incomplete. I take it that these 3 shafts were the same model in 3 flexes. There was no indication of launch angle and the spin rates were higher than I would like to see . There was also no mention of shaft profile, which can have more effect than flex.I hope to see more of these type of tests so the golfing public can be informed better through facts than absurd claims from manufacturers. Keep up the good work.


jmiller065 August 30, 2012 at 5:24 am

Exactly what I sort of was getting at in my post… something seemed WAY off about these numbers for the three players that have stats posted in here… I think a good lab would be three shafts that have the same “flex” with different tip profiles. Soft, Medium, Firm tips and see how that would effect the optimal results… Title it “Are you playing the wrong shaft profile?”


GolfSpy T August 30, 2012 at 5:40 am

Every time we do one of these labs articles we get one or two of you who tell us how we should have done it differently. In this case, the study was for flex, which as, everyone knows (for better or worse) is the most common variable used for shaft fitting.

Doing a test on tip profiles/stiffness is an entirely different article, although certainly it’s one that might be worth doing.

Can you give an example of numbers you think are way off? I’m guessing that anything that doesn’t meet your expectations proves the point the article made. All of the numbers are the result of direct measurements with a FlightScope X2. It doesn’t get much more reliable than that.

I agree, launch angle probably should have been included, but with the *possible* exception of player 3, with at least one shaft, the testers did achieve spin numbers within the reasonable range (assuming a launch angle also in the *reasonable* range).

But again…the point of the article was not to perform a club fitting. We weren’t trying to achieve optimum results. No one is going to achieve optimum results for 3 different golfers, when the only fitting variable you can modify is flex. We’re simply showing that the flex that many people assume to be the right fit for them may not actually be so.

While many of our readers are more educated, the average golfer is largely unaware of things like:

-Stiff does not equal stiff, does not equal stiff depending on the manufacturer, model, and whether it’s a made for or *real* variant.

-Most have no concept of things like bend point, torque, tip and butt stiffness. Again, the unstated assumption is that stiff = stiff = stiff, and that’s all there is to it.

With those two points lost, you’re already fighting an uphill battle with the average golfer.


jmiller065 August 30, 2012 at 11:34 am

T, let me back up for a minute here… this is an opinion board / comment section isn’t it? I thought that opinions were fine on this site or am I missing something?

You know as well as I do there are not any standards to “Reg Flex”, “Stiff Flex”, “X-Stiff Flex” on a label the Butt Frequency needs to be taken to get a literal measurement for stiffness in Butt Frequency. You might be sitting there with what you assume is a “X-Stiff” but it really CPMs to a “Stiff”… Take one of my driver shafts for example the label says “Stiff” but the CPM is 274 raw more of an X-Stiff CPM. So one thing missing from this lab is a validation of each flex at the playing length.

Also, you know as well as I do that tip profiles can be different between the same shaft model and flex let along the tip profile between the Regular compared to the X-Stiff. Do we know what the bend point and tip profile happen to be on the 3 flexes, not a clue. It wasn’t included in this “lab” so maybe it needed added to be able to draw more of a conclusion for the flex and profile.

I was only pointing out that the spin rates don’t fit the players and are not optimal in all flexes… Which like slimjim pointed out the shafts would be completely ballooning for a player and is just a bad fit regardless of the flex in this situation… It is my opinion that we give the correct information to people and not make assumptions on what they can comprehend or know about a subject…

I find it really hard to draw a conclusion that I am playing the wrong flex based just on what is provided here, their is more to the puzzle then just flex and you know that. The general public needs educated on that fact as well so why not educate the masses in the process?


GolfSpy T August 30, 2012 at 11:59 am

J – I think you misinterpreted my reply. I wasn’t sure what numbers you were questioning. Yes..spin numbers in some cases are high, but I did want to make sure you weren’t suggesting the measurements themselves were off.

We don’t disagree on much here, but my feeling is that you want this article to be more than it was intended to be. In hindsight we could have included a bit more background about the extremely popular misconceptions that 1)Flex is the most important (or only fitting variable) and 2) Proper shaft flex can be determined exclusively by swing speed.

Tip stiffness, but stiffness, bend profiles…all of that while very important, aren’t missing, they’re simply beyond the scope of this article (since I know what you do for a living, I’m reasonably certain you’ve dealt with more than your fair share of requests from outside the scope of the project).

The point of this article was very simply that swing speed alone is a very poor way to determine proper flex, and the article basically shows that.

Your knowledge is vastly greater than the average golfer…the guy who buys off the rack and basis his flex determination based on how hard he thinks he swings. We can’t be all things to all golfers all the time.

Simply put this article was for that guy, and probably is not for you.

For what it’s worth, the shafts we received were blacked out, and only Matt knew which flex was which, but I’m reasonably certain that they are UST ProForce VTS Silver, which is which UST considers mid-torque.


jmiller065 August 25, 2012 at 6:43 am

I am not sure how much I trust these numbers. However it does illustrate a good point that some people regardless of swing speed will not fit into the suggested flex. Really flex is mostly about how much transition load and release load you place on the shaft not really a SS so to speak. Take Luke Donald his SS / numbers suggests that he play a x100 soft stepped one time, but instead he likes the feel of a s300 better because he has a smoother transition.

First, I don’t see how these numbers are accurate for the ball speed and swing speed listed. I don’t see how they could possibly be the total distance for the 111mph SS/ 160mph BS player. If you make the assumption that they are carry numbers we get closer to the distance numbers listed.The best I could get out of the optimizer with 3100 RPM at 14 to 19* of launch angle and a 150mph ball speed is a 249 carry. The best I could get from the optimizer with a 142 ball speed and a 15* to 19* launch angle was a 230 yard carry. If you plug in the 111mph SS / BS data and tweak the launch angle you can get the exact carry distances that the ball was supposed to have gone and it matches up with the distance that is listed.

Secondly, to me it is pretty clear that this shaft spin WAY too much in the head being used for all three players testing these shafts compared to optimal. I don’t have their exact launch angles but I do have what needs to happen to maximize carry and total distance for all 3.
–> 150mph ball speed, 14* launch angle, 2450 to 3000 gives a 249 carry… If you increase the launch angle and decrease the spin you get even more out of it. Example: 2150 – 2700 is a 253 carry.
–> 142mph Ball speed, 14* launch angle, 2800 to 3000 RPM gives a 231 yard carry… Change that Launch angle to 18* and 2200 RPM you get a 238 yard carry.
–> 160mph Ball Speed, 14* launch angle, 2450 to 2600 RPM gives a 273 yard carry.. Change that to a 16* launch and a 2100 to 2400 RPM spin you get a 277 yard carry.

Last, In short there is a trend, launch the ball as high as possible while keeping the spin as low as possible. You have to find some middle ground, for me that happens to be about a 12.5 launch angle. At a 168mph ball speed, I need to keep my spin around 2400 to 2900 to be in optimal carry of 287 yards. I i get the launch a little higher to 13* 2300 to 2800 gives 288 yard carry. If I can get the launch a little higher to 14* and the spin into 2100 to 2700 range its a 290 yard carry.


JJ August 24, 2012 at 5:44 pm

has anyone given any thought to the fact that a lot of shafts are produced out of china-and maybe the quality control isn’t what it s/b???
I have heard from a local club fitter who know shis stuff that a Tm shaft marked stiff was actaully a ladies medium..
we all know that the main mfgers use China as their main manufacturers, has any one got “the guts” to actauul expose what is actually coming out of China in terms of quality control???
i know i have check Vokey wedges for loft angles and they are off by as much as 3 degrees-what that????
Wht hasn’t Golf Digest etc-looked into this?????-oh Yes I know why because they are their major advertiser!!!!
Crap is


Marcel V August 24, 2012 at 9:23 am

A good reason to understand, why we need a site like this, great job


Mark August 24, 2012 at 7:17 am

First of all I’d like to say this was a great article. I agree with Bill, it is very clear that there are a variety of variables in a golf swing that make a world of difference towards overall perfomance. Although your three testers are a good representation of the “average” golfer, it is very difficult to get true results unless you have a repeatable golf swing. Now that does not mean you have to have a “perfect” swing ie; center hits on club face, inside-out, late wrist cock and upward angle of attack, but whatever swing you have it must be somewhat repeatable for measuring purposes and to draw some sort of general conclusions. It might have been interesting to see results from robot testing of similar swing speeds as your testers to see if there were similar discrepences. Keep up the good work.


The One Swing August 24, 2012 at 5:20 am

Not everyone is a single digit handicap, and I think for casual golfers whose swings will change from hole to hole, personal preference is just as important as a recommendation from a fitter. I think articles like this are important, but I find personal preference affects confidence much more than someone else’ opinion about what to hit. Club fitting isn’t an exact science. You have a bit of the club fitter’s personal bias affecting the recommendation every time. Because if personal bias wasn’t a factor, then you should be able to go to any fitter and you would buy the same 2-3 clubs/shaft/flex no matter who you saw. Also, pretend your fitter has short term memory loss. Would he recommend the same club/shaft/flex every time you saw him with zero variation? Probably not. If that’s the case, then you get into the argument of “X fitter guy is better than Y fitter guy.”

At the end of the day, the guys that take their game seriously enough to seek the advice of a professional fitter will do so, and the once-a-monthers will buy the club that they find visually appealing with a flex that they enjoy hitting. The people that play semi-annually and consider low 120s a good score for them won’t improve their game by getting the right flex.


Kevin August 24, 2012 at 1:19 am

I cannot read anywhere in your report to say if the clubs were tested for Frequency (CPM’s) and Swingweight! Or did you just except that the shafts were Regular, Stiff and X-Stiff and equal Swingweights?


leftyjohn August 23, 2012 at 5:44 pm

Excellent overview on the fitting of flexes with human body variables. A few years ago, Callaway introduced the I-mix system for equipment ‘Hos ( like me) so we could try, and try and try combinations that were self-inflicted or self-mutilating. I was “fitted” with a cally diablo octane tour 9.5 with a Project x 6.0 at a big box store. I confirmed the fitting in Vegas at their fitting centre while on vacation. However,as sweet as the numbers on the monitor, I couldn’t help myself from trying other combos, like 10* draw FT9 with a xstiff 83 white board. that too is sweet, cause the draw head cancels the slight fade caused by the stiffness of the shaft. But my favourite feeling shaft is an Aldila NV 65 green regular flex. Not quite as long, but “comfortable”. My SS varies from 95-105, so it crosses the flex “zones of confusion”. So now I just keep trying shafts and different heads, searching for the ideal. As a 63 year old lefty, it’s not as daunting as it is for those “less gifted”, but the Wishon and/or golfworks “maltby playability factor” is a good place to start.


Martini August 23, 2012 at 4:24 pm

Despite all of this info out there it still surprises me how many customers don’t realize the value of fitting…..however your article just touches on flex, and unfortunately there is a 20 point difference between the top end of flex and the bottom…..thus quite a variance. Torque and tip stiffness are also variables the consumer needs to be aware of in terms of accuracy as is gram weight. Too often customers get caught up in what the shaft says as opposed to where the shaft frequencies. Most players would have a difficult time feeling the difference between a stout regular and soft stiff, but 2.1 torque rating with a stiff tip and a 5.2 torque rating with a softer tip might influence feel and performance in the same shaft flex.
Yes the need to get fit NO MATTER skill level is very important…..unless you enjoy frustration on the golf course.


NOJO August 23, 2012 at 3:42 pm

The number of variables is endless: Loft, club-head COG, Moment of Inertia of the club, Swingweight, stiffness profile, overall shaft weight, shaft balance point, shaft length, face angle, angle of attack, tempo, club-head speed, rate of acceleration at impact, club-head path, and on and on. Ball flight [measured and perceived], and ‘feel’ are the only really reliable ways of selecting a driver head/shaft combination. Perhaps ALL drivers should be purchased at driving ranges, from among ‘gently used’ demo clubs in a ‘Gently Used Demo Driver Shop’, where a customer gets to road test all the drivers he needs to before selecting that ONE which is configured exactly right for HIM. Install a new grip, take his money, and send him out the door with the perfect club!


Bob August 23, 2012 at 9:58 am

How about sht dispersion. How did flex add or hinder accuracy?


jmiller065 August 23, 2012 at 12:18 pm

Just from the 3 players posted you can see that 2 of the 3 had the tightest Dispersion with the X-Stiff… Somehow the 111mph SS managed a super tight dispersion of the Regular Flex. Most of the time as the flex increases the shaft won’t have as much dynamic lead / dynamic close into impact. And a lot of times as flex goes up the torque ratings go down slightly. It would make since that most people would show a tighter dispersion with a shaft that fits and maybe tighter with one too stiff.


carey moluchi August 23, 2012 at 9:23 am

An interesting discussion indeed. A further comment I would like to add with respect to testers is that women also shop for golf clubs and would like to be included in the testing. Like men, there are huge differences in strength, height and skill levels and corresponding shaft choices. Contrary to some beliefs, not all women will play with a ladies flex!


Fozcycle August 23, 2012 at 9:10 am

I guess that’s why I am using a PX 5.0 in my Driver; Callaway Stiff in my 3W, 3H & 4H….all of them being the Callaway FTiz models…….the result is longer, straighter shots than before with just Regular shafts.

My Swing Speed is 87 mph for my Driver.

I do feel a bit more confident now that I know I am not crazy.


Justin August 23, 2012 at 9:02 am

I love the shaft optimizer from Mizuno…if it is used correctly! Many big box stores use the software and just pick one of the recomendations. You need to hit the 2-4 shafts it shows and confirm whats best for you.


RoverRick August 23, 2012 at 8:58 am

I have been pissed of for months at the “fitters” I have been to because they sold me on the wrong shafts for years. Because my slow swing speed I needed a regular shaft, and because I had a regular shaft I needed a slower swing speed. Finally, have the right shafts and having a great season.


Bill August 23, 2012 at 8:37 am

There are too many variables with individual swings. When testing, I would opt for a machine based swing to see how flex equates to the same swing motion at different speeds. From there, one can take the data and use it when getting fitted.


Rev Kev August 23, 2012 at 8:46 am

You mean use a robot? :)

Couldn’t resist.


Robert August 23, 2012 at 8:33 am

Have to mention I was fitted for some Mizuno mp59’s via the Mizuno Swing Test shaft attachment. I was told I required a graphite regular flex. Bought the clubs, absolute rubbish, they were returned within a month. Went back to a heavier steel shaft, kept to regular though, have tried stiff but I get no advantage. I am for some reason a very straight hitter and play off 3, I do not bomb the ball like most other players, I drive it 250-260, very rarely get outdriven by the ‘I hit it 300+ brigade’ . I would also like to mention that popular believe here in the UK is that if you are a long hitter you must be a great golfer. I have found my average distance and superb short game added to my ability to putt ( lots of practice involved )has got my handicap to where it is. I still find many of my partners buying stiff shafts because thats what they do, I really feel a regular shaft if more benificial to the average golfer.


GarnetinOZ August 22, 2012 at 7:53 pm

So does all of this suggest the potential for me to need a different flex for my Driver and irons, depending on Brand of shaft? I have just been fit for a set of irons and the flex was based on my swing speed 62- 67 mph with a 6 iron (picking clubs up today …Cally Razr X Black w/ Cally Uniflex Shafts).


GolfSpy Matt August 24, 2012 at 12:46 pm

Potentially, yes.




Brian August 22, 2012 at 11:58 am

Neat study


Kevin August 22, 2012 at 8:32 am

Is the shocking part that you estimate over 50% of fitters are fitting the wrong flex?

Seriously, there are too many differences in flexes from shaft makers to make any generalizations.


Lou August 21, 2012 at 8:28 pm

Last year I took a long vacation that had at its heart a desire to get fitted properly for a full set of clubs. I committed about $1,500 to getting fitted for, and buying the best set of clubs I could afford. I got ’em alright …..and three months later they were on eBay…..didn’t like either their performance or looks.

I did use what I learned on my iron fittings to adjust my lie angle to a -4, which has helped me particularly in my short game, but the fact is that I was already playing the best clubs I could for my game, which I actually only bought because I liked their looks and the color of the shafts.

Unfortunately I went through about five different sets of irons before I finally got smart and found (on eBay of course) a duplicate set of the ones I sold before my infamous vacation. I have changed my woods based on the specs I got in my fittings, although what I ended up with was Cleveland’s instead of Pings because i get a lot more roll with the Cleveland’s.

So the conclusion? I believe there’s nothing like trial and error for us regular golfers……learn what you can obviously from fitting, practice, lessons and reading, but nobody has enough stuff for you to guarantee you’re getting the shaft or club that’s perfect for you today…….and as you age and perfect your swing, what is good today may not be tomorrow.

As a final note Matt, at my prime my driver swing was 92 mph, which produced enough distance for me (5’5″ and about 150 lbs) to be among the longer players in my group . Today that’s down to about 82 mph at age 68, and I’m still the longest driver among the ten or so guys I play with regularly, all with handicaps between 10-16 and in their mid sixties. Personally, I don’t know if there’s any data supporting the averages, but on your website (fantastic by the way) and the WRX site there seems to be a lot more emphasis on the guys who can hit it 300+ than what I think the “averages” would support. In all my years I’ve know a heck of a lot more guys who fall between 250 and 280 than those who can hit it further. Could you please start including some seniors with mid or or low eighty swing speeds in your testing? Thanks and keep up the great work.


Golfspy Matt August 22, 2012 at 6:04 am


Thanks for sharing your story, and thanks for reading.

As far as the distances people hit the ball, you’re absolutely right: everybody exaggerates. I’ve read numerous accounts that state that the average American male hits their average drive 200 yards, yet I only teach 1 guy (out of 100+) claims that his drive goes anything short of 230. Nonsense.

With regard to getting some testers with swing speeds in the 80’s, I can only tell you that we’re trying. As T said in his “MyGolfSpy responds article here:

We are trying to expand our pool of testers, but we run up against a couple of tough realities:

1) Time and money are very limited. We can’t compensate testers and scheduling can be tough.
2) It’s hard to find testers who can consistently put the club face on the ball. I have a couple of people I know who are good enough players to create valid data, and so I tend to go back to them.

All that said, it’s a valid point and something we’re trying to work on.

Thanks again for the feedback.




Rev Kev August 23, 2012 at 8:53 am


I’m a low handicapper with a swing speed between 90-95 and a flexible albeit crazy work schedule. I think I hit the ball as consistently as most. I would never expect to be compensated for testing. Just saying.

The downfall is that I live in Florida but so do lots of other golfers from our MyGolfSpy community.



Yohanan August 21, 2012 at 7:58 pm

Fo sho. Its about the shaft and when you load it and angle of attack.Yet is by far the best -for me . V2 is solid. Anyway great article. And for all those fitters out there – there is a shaft/club for the MY / YOUR swing.

Don’t settle for less.



wdgolf August 21, 2012 at 3:46 pm

Very interesting results. I’m curious, do any of the high swing speed players on tour use a S flex shaft?


Golfspy Matt August 21, 2012 at 5:00 pm

Interesting question. Just from thinking back on “WITB” articles I’ve seen, I can’t remember any pros who play stiff flex in their driver. I did see something recently about how some pros are moving to stiff in their irons instead of X.


Rev Kev August 23, 2012 at 6:22 am

I’ve noticed the same trend – S popping up in the irons of tour players. I’m wondering if their X flex isn’t mitigated by the way the tip is trimmed so that they cover the tweener needs.

I’ve written in other places that I was recently fit through the bag for the very first time – the fitting was done by a combo of a fitter/club maker and a teaching pro. My swing is pretty good (hence the low handicap). It does not produce nearly the clubhead speed that I would like given what other people report but that’s neither here nor there.

The fitter/builder ordered R flexes for me but told me that the way he installed them they are really inbetween S and R. I don’t pretend to understand all of this – what I do know is that after a set back for a serious illness in the late spring I’m playing perhaps the best golf of my life – My last five rounds have been 71, 76, 71, 69, 71 – that equates to even given the courses the pars of the courses that I was playing.

I was sick, I’ve had little time to practice because of a combo of the weather and work, I’m putting well but not spectacularly so – the only possible reason for those scores is that my equipment fits me – my average score the past couple of years has been a shade over 76.


RP Jacobs II August 21, 2012 at 3:39 pm

Excellent article Matt…Hopefully some will listen, and themselves a favor the next time they purchase a club(s)……

Fairwasy & Greens 4ever……….


Christian Furu August 21, 2012 at 1:42 pm

Great article. Flex code – like you can find on Miyazaki shafts – are for me a better way to find a good shaft. They have stiff flex shafts with softer tips than their regular flex shafts. It´s all about the properties of the shaft and what your swing needs.


BK in Wisconsin August 21, 2012 at 1:41 pm

Another example of why this site rocks!


Sandy R.Karse August 21, 2012 at 12:08 pm

I am a male, hit left handed and my handicap floats from 15-21, swing speed with driver is around 85-90 miles per hour, etc, If I swing to fast I have a tenency to hook the ball.. I play with seniors Harrison Graphite Shafts by Warrior Golf out of California,,, Any suggestions to hit it straightr and farther.. Have lost distance over the years, I am 79 years of age, 5’10” tall and weight 145 lbs. Look forward to your recommendations and do enjoy your emails, best regards, Hear From You ASAP, Sandy R.Karse.


Marty August 21, 2012 at 10:24 am

Yesterday I read some info about TGM somewhere online, in the TGM book by Homer Kelley there is a paragraph Ref 6-C-2-C (Impact Cushion).

Do you have the shaft loaded/stressed on impact or not.

A slow swinger with a 10.5/regular low kick point driver may hit better/further with 9/stiff driver mid kick point if his shaft is not loaded on impact.

If your action is not delivering lag, ie a stressed shaft at impact, then all the shaft will do is cushion the impact per 6-C-2-C.

In a non lag situation, a stiffer shaft will cushion less, and a more flexible shaft, particularly with a low kick point, will bend back and cushion more.

Under these conditions, a stiffer shaft with a mid kick point will perform better than the standard prescription

In other words, what you get from the shaft depends totally on whether you have it pre-stressed (lagged) or not!!

Now that totally different then most people will tell you..


KFlare August 21, 2012 at 11:02 am

After getting a great driver fitting at Conquest Golf, I learned this too. Apparently a huge factor for shaft fitting is early/late release of the clubhead!


David W August 21, 2012 at 4:08 pm

That really makes a lot of sense.


Golfspy Matt August 21, 2012 at 6:22 pm

Please watch Season 4, Show 3.

The shaft (regardless of flex and swing speed) is in LEAD DEFLECTION (head in front of the grip) at impact, not behind.

That does not mean that early or late release may not be a big factor in shaft fitting, but it’s important to understand that you can’t add force to the shaft through impact.




BR August 23, 2012 at 9:02 am

Yes this is very good information although complex for most golfers and non TGM/analytical instructors (nothing wrong with either approach as long as it addresses the golfers needs). I use TGM and what Wishon is doing with his shaft designs to test which characteristics of shaft design/fitting methodology fits my swing. Plus I can better distinguish commonality between shaft manufacturers designs before purchasing a shaft/driver.


Cobra nut August 21, 2012 at 10:09 am

I was fit when I purchased my Cobra ZL driver 8.5 loft UST Tour stiff shaft and it felt great to me, I average 106mph swing speed and 260 yard drives with this set up. I went to another pro shop and tried out a new Cobra Amp with the stiff Rip shaft in a 9.5 degree and was surprised to see my distance drop a little, so the staff member said “hey just for kicks try this 10.5 degree driver” and did, well I was a lot confused after hitting this set up, the ball launched lower than I expected and it gave me on average another 12-15 yards distance with only about 5-10 yards left to right difference. I think now that not only is the proper shaft fitting important but the proper shaft to loft according to your swing is just as important. Just joined this sight and thank you for this great write up you do amazing articles and I love to read them all.


David W August 21, 2012 at 10:04 am

When I was fitted for my G20 my swing speed was measured at 98 mph yet I was fitted to not only a stiff flex but a tour stiff flex because of the flex point. It was simply because I tend to hit a driver very high. The tour stiff flex brought my launch angle down to where it should be and my distance increased along with cutting out a lot of my fade. I can actually draw this one (sometimes) if I need to.


KFlare August 21, 2012 at 9:31 am

This is pretty fascinating. For me, it reinforces the wisdom of Accra and UST (and maybe others) for making shaft families with lots of small variations like tip stiffness and torque. It seems this is the best way to give more control to a skilled fitter. How in the hell is someone supposed to reliably compare a Fujikura “this” against an Aldila “that” when they all use different standards for “stiff”???


Rev Kev August 21, 2012 at 9:31 am

It becomes more and more apparent that fitting is part art, part science.

Plus we haven’t even got to the inbetween flexes that can be created based on how the club is assembled by the builder once the fitting is done.

I’m not a fitter but I have a friend who was recently fit for a stiff shaft – his swing speed calls for it – but he’s a very smooth swinger of the club – I can hit his stiff shaft straight as a arrow (I have a more abrupt transition) he can’t. I told him to consider getting a regular shaft – he has and he’s hitting a lot more fairways – a lot more fairways.

Great piece.


Nevin Wilson August 21, 2012 at 9:12 am

Is there data of this kind for irons and for steel shafts? It almost seems like we are back to trial and error when it comes to selecting the best shafts, perhaps using a Trackman or some other device but still trial and error. Like Bobby Jones picking his hickory shafted clubs out one at a time based on feel and performance, only now the shafts are graphite. I guess the first question is where should we start? How long is it going to be before this kind of data is known to the typical golf club fitter? – Nevin


GolfSpy T August 21, 2012 at 8:24 am

Unfortunately the industry (including most shaft companies) still uses swing speed as the primary fitting variable. This is why you’ll those silly little charts that recommend flex based on a swing speed range. Not only does that not begin to cover all the bases, I’d argue it’s probably not even the best place to start, but…

Unlike most other fitting variables, swing speed is easily quantifiable. Tempo and transition…what does smooth mean? What does aggressive mean? While we might all have our own unique understanding, these ideas don’t translate well to a simple little table format.

It’s a little sad because the result is the majority of golfers take on the mindset of “I swing 96 MPH so I need a stiff flex shaft”. Many don’t consider things like bend point and torque.

As an example – one of our former regular testers (Dan for those of you are curious) is a PGA apprentice who plays to about a 3 index. His swing speed tops out around 114 MPH, and he routinely hits the ball over 300 yards (his average is probably in the 288-292 range). On most every chart he should play an X-flex. What the static fitting doesn’t account for is Dan’s smooth tempo, and very controlled transition. Despite swinging 7+MPH faster than I do, Dan places significantly less load on the shaft than I do. He routinely produces his best numbers with a softer (S-flex), while my numbers, despite the slower swing speed are generally better with a stiff tipped, X-flex. And all of this is before we start talking about shaft weight.

I don’t have any hard data, and full disclosure, I haven’t even run this by any of the fitters we work with, but…based on my own fitting experiences, and my observations during our countless testing sessions, tempo and transition is where the demands are placed on the shaft, and are both, in my opinion anyway, much more important in the fitting equation than swing speed alone.


Dave August 21, 2012 at 8:16 am

I admire the effort and agree with the conclusion even if the methodology is flawed. IMO the term shaft flex has no place in modern custom club fitting and should be replaced with a more meaningful shaft categorisation system such as Miyazaki’s International Flex Code (IFC).


Dronsky August 21, 2012 at 8:11 am

Great article! When i was working in a golf shop i found that the shaft flex was the least of the customers worries, which worried me! I don’t think people understand how a shaft can affect the entire club, weight, feel, and also performance. I just recently decided to try a Pro force V2 X-stiff 88G because i load the club so much with a quick tempo, and it dramatically affected my driver now “swinging easy” is 300+ and on saturday i hit one 350 with a perfect fade. Take the time to go get fit and try as many clubs and shaft combos as you can!!!!


TheGreekGrind August 21, 2012 at 8:06 am

I switched to Project X 6.5 shafts in my irons this year (and even shortened them, ie, from 39″ 3 iron to 38″), play the AD-DI 7X in my driver and fairways, and AD-DI 95X in my hybrids.

And I can say 1000% I’ve never hit any of these clubs better. Which is not to say this is true for everyone, but it is certainly false that you have to be a beast to play X flex shafts. That’s absolutely laughable.

There should be a “reasonable golfer” standard applied to opinions and claims that get passed off as truth – just as there is a “reasonable man” standard applied in the law. Because quite honestly some claims out there are absolutely ridiculous and border on rubbish. I’m tired of seeing so much misinformation, and puffing, and general nonsense comments that get passed off as “helpful fact based information.”

Well done MGS again laying it all out on the line and giving the cold hard facts.



tider992010 August 21, 2012 at 5:55 am

This is exactly why there should be some standardization in golf for shafts. Each company has different standards. Get fit!!!!


Mikerio August 21, 2012 at 5:34 am

Well done! I asked a student at work to try this out for a project he was doing and he looked into how older club heads stand up against newer models instead (by the way in terms of irons he found guys carrying older ping irons, for example, had far more success!). I used to teach a kid who has just turned pro…..he told me that when buying irons, woods whatever….he would research shafts first…..he said that we are all obsessed with clubheads when they play a only a small role in improving your swing. I’ll be honest last year i bought a callaway diablo edge from walmart…..just picked it up and bought it….sold it few weeks later. I went into edwin watts and just bought a GI5 hybrid……didnt even hit it…….its took me forever to get used to the fella. Im buying a 5 wood this year and will take my time with the guys at the shop before i buy…….patience is a virtue!


Westy August 21, 2012 at 4:18 am

The worlds gone mad, what can we now believe in? I’d be interested to see the results with a 7 iron I think, with a driver I’d spotted this before for myself. Not a fast swinger, sub 100mph but the longest driver I’ve ever had was an old r7 with an x stiff in it. Logic told me it must be a fluke so I ignored it.

Only thing is how many of your average golf pro’s understand this?


GolfSpy Matt August 21, 2012 at 7:43 am

“Average golf pros” as in club pros and guys who recommend equipment? Not a lot. And some of them may know a little of this, but aren’t interested in educating people (and, having done the retail thing, I don’t entirely blame them. When a guy comes in thumping his chest that he wants a stiff flex and won’t listen to anything you say, you sell him what he wants and move on).

That’s why MGS is here: to educate the consumer. Ultimately, it’s YOUR game and they’re YOUR clubs, so YOU should be educated and know what you want or need for you game.

Thanks for reading.




TwoSolitudes August 21, 2012 at 3:45 am

And this is why I keep coming to MGS. A great read that will leave many scratching their heads. I am must admit to being guilty of trying to follow ‘common wisdom’ without ever getting the results I thought I would. I was convinced that the softer shaft would always mean more ball speed and that a stiffer shaft would always give you less spin. Neither seems to be the case here.

But if every golfer reacts to shaft flex differently, how can the OEMs even start to market them as suitable for X type of golfer and how can a golfer know where to start? Are there any truisms in shaft builds, or is the connection between each golfer and each shaft completely unique?

Maybe I should try out a X shaft just for fun.


GolfSpy Matt August 21, 2012 at 5:47 am

TwoSolitudes: Thank you for the kind comments.

As to your question, I have hit more different shafts in the last couple years than I ever imagined possible, and I truly believe that the connection between the player and any given shaft is unique. I have tried stiff flex shafts that I hated. I’ve had X flex’s that I loved. There were shafts that “should have” fit me that I wouldn’t have played if you paid me.

One thing I have found is that I tend to like or dislike brands of shafts. I’m not sure if that comes down to design philosophy, materials used, manufacturing technique, or, possibly, some biases I have in my brain.

Ultimately, I keep falling back on the same refrain: go get fit. Try a lot of stuff, see what you like, and see what works. Go in with an open mind and test everything you can.




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