November 26

Golf Shaft Fitting: Swing Speed

Golf Club Fitting


When you're fitting a golf shaft, swing speed is but one part of the overall equation.

Yes, it's important.

No, the faster you swing doesn't equate to a stiffer flex.

No, that wasn't a contradiction.

When you're getting a golf shaft fitting, swing speed is only 1/3 of the process for finding the right flex; so what else is there?

Find Your Recommended Swing Speed Range

First things first: you have to know for sure what your swing speed is.

The reason is, every shaft has what's called an RSSR, or "recommended swing speed range".  Take a look:

The chart is for the Kuro Kage HBP 60, which you can see the chart-and buy- at Diamond Tour Golf (non-affiliate).  Check that middle column; what do you see?

RELATED: Don't want to spend more than $50 on a golf shaft?  Check these out!

That's the recommended swing speed range for each flex they offer for that particular shaft.

At its most base application, if you have a swing speed somewhere between 90 and 100 mph, you could use the Kuro Kage in S-flex and it would work for you.

But of course, it's not that simple...

Look, this article focuses on swing speed, but to do the subject justice, you have to know about the second of the three factors: the transition.  

Don't fret, though; the third part is going to get its own article, so I can do that more justice.  For now, though, these first two parts go more hand-in-hand, so they should be kept together. 

How do you transition?  What is the transition?

When you're getting a golf shaft fitting done, any fitter worth their salt will be taking a close look at your transition, how you start the downswing.  

If you want to do this yourself, record your swing and focus on the point where the backswing stops and the downswing starts.  What does it look like?

There are three basic transitions:

  •  Smooth; AKA: Passive
  •  Normal; AKA: Medium
  •  Fast; AKA: Aggressive

I've mentioned it before, but it should be repeated: how much force you put into your transition will have an affect on what shaft flex you use.

For a refresher:

Let's say our example golfer is you.  If you're sitting on a 95-mph swing speed, but you have a passive transition, you might actually find you're better off with the R-flex.

The reason is, the less force you put into the transition, the more help you're going to need to feel the club head lag.  Going to a softer flex can help with that.

Conversely, if you have an aggressive transition, you'll likely be better off going to the X-flex.

The reason for that is because of your forceful move, you'll be exerting more "oomph" on the golf shaft.  If it's flex is too soft, you can mess up your swing timing by having it flex too much when you start the downswing.

Do you see how the transition affects your swing speed?

Not directly; a 95-mph swing speed is still a 95-mph swing speed.  But it does indirectly impact the shaft you choose, based on your swing speed.  If you have a passive transition, you effectively have a slower swing speed; if you have an aggressive transition, you effectively have a higher swing speed.

There's a little more to shaft flex than you might've thought, isn't there?

When you're getting a golf shaft fitting, swing speed is a good number to know.  The REAL number.

Look, I'm not trying to make waves, but unless you use a device to measure your swing speed... I'd bet you don't know what your swing speed really is.

If you don't have access to a fancy launch monitor, even a $150 Voice Caddy SC100, you can guesstimate what it is with the help of your 150-yard club.

Do you know which club's your 150-yard club?  I'm not talking total distance, though; what I mean is, if you're 150 yards from the center of the green, and you intend to land the ball on that spot, what club do you use?

Here's a quick-reference golf club shaft flex chart (thanks to GolfWorks) you can use, once you figure that out:

Club Used From 150 Yards
Estimated Swing Speed (MPH)
Expected Shaft Flex
3, 4, 5 iron; hybrid



6 Iron



7 Iron



8 Iron



9 Iron or Wedge



For your swing speed in the example, you'd get confirmation that you should at least start by looking at the S-flex.  Now, just figure out what your transition is like to fine-tune the rest!

If you ever need to see this chart, just click HERE to get it.  Just make sure to bookmark it!

RELATED: Ever feel like you're wasting money on golf shafts?

The Release- The Final Third of the Equation

Keep an eye out for the final third of the equation!

About the author 

Justin Blair

Justin Blair is the founder of Green Lantern Golf. When he isn't bringing his 10+ years of excellent craftsmanship experience to golf club fitting, building, and repair, he's geeking out about Star Wars (he's watched them all about 8,437 times!) and things like the MCU and LOTR, he's drinking mead and craft brews. If you wanna know more, check out my About Page!

You may also like

Swingweight- Why You Should Care

Fix Your Golf Swing With Proprioception

{"email":"Email address invalid","url":"Website address invalid","required":"Required field missing"}

Check out the Green Lantern Golf Store!

Wishon drivers and irons, Inazone wedges (for lefties!), and more!