Rather than focusing on smash factor, focus in on ball speed, launch, and spin. Marty Jertson explains why smash factor can be a flawed metric.
Both radar-and camera-based launch monitors are quite amazing. They’ve come a long way in the last decade, and probably will keep advancing in the future. Radar-based systems, such as TrackMan, can virtually “see” around and over objects and fuse radar signals with cameras together, like Tesla’s self-driving technology, provide precise ball and club-tracking measurements.
As good as contemporary measurement systems are, some metrics must be used with caution. And, even though it has a cool name and is easy to use, “Smash Factor” is one metric that can distract you from what’s really important during a club fitting or club comparison.
This article is a cautionary tale about Smash Factor, and why you should look beyond this metric when fitting your customers.
Many fitters use Smash Factor to assess the “efficiency” of an iron or driver, and use this to determine whether one club is better than another. Smash Factor is calculated by dividing the ball speed by the clubhead speed.
THE MOST VALUABLE PARAMETERS DURING A DRIVER FITTING ARE BALL SPEED, LAUNCH ANGLE, SPIN, AND DISPERSION – AND HOW WELL YOU MATCH THESE WITH YOUR ATTACK ANGLE.
For example, if you swing a driver with a clubhead speed of 100 mph and generate a ball speed of 150 mph, the Smash Factor is 1.50. So, the higher the Smash Factor, the more ball speed you are getting for a given clubhead speed. Launch monitors give values that typically range from 1.3 to 1.4 with a 7-iron, and 1.44 to 1.52 for drivers, depending on the model, head weight and launch monitor in use.
The idea of Smash Factor has its place and sounds like a fun value to maximize, but the most valuable parameters during a driver fitting are ball speed, launch angle, spin, and dispersion – and how well you match these with your attack angle.
Likewise, when evaluating irons, Smash Factor can be misleading due to loft or head weight differences between clubs. You do not want to mistakenly choose an iron based on a higher Smash Factor instead of the one that provides higher peak trajectory, more distance, better turf interaction and tighter dispersion–the real metrics that can help you Play Your Best on the course.
To get a precise Smash Factor value, you need a precise clubhead-speed value. This sounds simple. But what is simple is not always easy. Why? It turns out that clubhead speed is a very tricky thing to measure.
For one, we must ask, which part of the clubhead’s speed are we measuring? Because the club is rotating and closing rapidly as it approaches the impact zone, the toe of the club is typically travelling about 10 mph faster than the heel. This makes determining the exact speed at the centre of the face very hard to determine, regardless of which technology your fitter is using.
Some launch monitors today, however magical they seem, make measurement errors for any number of reasons (unique head shape or features, clubhead mass, face closure, etc.). Small errors in the clubhead-speed reading can cause you to be misled if you are Smash Factor focused.
Which is better? At 1.50 Smash Factor, you or your fitter may be initially inclined to say Driver A is “more efficient”. But, at 6 mph faster ball speed, Driver B will assuredly go 8 to 10 yards farther, all other things being equal, even though the Smash Factor ‘appears’ lower. So, don’t be fooled by Smash Factor.
AT PING WE DON’T LOOK AT SMASH FACTOR DURING FITTINGS, AND YOU SHOULDN’T EITHER.
Here is what you can do: Tell your fitter that you don’t want to look at Smash Factor. Remember, ball speed is king. For drivers, focus on increasing ball speed, optimizing launch conditions (launch efficiency) – then try to minimize your shot bend and dispersion within reason for your swing. For irons, look at the peak height, landing angle, carry distance and dispersion, while being mindful of turf interaction and gapping.
PING G425 Driver
Our driver technology can help you with all these ingredients to driving distance. The aerodynamics will give you clubhead speed, the T9S forged face technology will give you ball speed, the CG shifter will give you less shot curve, and the high moment of inertia (MOI) will give you tight dispersion.
Vice President of Fitting & Performance
Marty has worked in golf r&d since 2004, including roles as chief engineer and senior designer, and is a named inventor on more than 125 patents. Marty is also a class A PGA member and has played in six major championships. He made the cut at the 2019 PGA championship at Bethpage Black, and competed in the 2020 U.S. Open.