Is Mizuno Mastering the Driver?

Its irons have long been its most attractive products but its drivers have had their admirers. The ST-MAX 230 will add to their number

By Tony Dear

If it seems like Mizuno comes out with a new ST (Speed Technology) driver every few months or so, it’s because by staggering its releases it comes out with a new ST driver every few months or so.

That’s just the way it likes it – keeps the mark of the ‘ST’ fresh in the mind, but also gives the impression the tech is evolving rapidly and every new iteration is significantly better than the last.

That’s not necessarily the case, of course. The ST-Max 230 is really another child from the same family so to speak. There’s a lot of overlap from previous clubs. So while it may not offer something entirely new and innovative, it does offer something different.

For starters it looks very different from the last driver Mizuno released – the ST-G which appeared last fall. Not only is the ST-G all-black with none of the blue accents of the ST-MAX 230 (and other ST drivers), but it also features two sliding sole weights unlike the ST-MAX 230. And, at 440cc, it is noticeably shorter from heel to toe and front and back than the ST-MAX 230 while also being quite a bit taller/deeper – Mizuno called the ST-G “squat”.

The ST-MAX 230, in contrast, is 460cc (the same size as the ST-X and ST-Z released in January 2023) but looks even bigger than that. By being much shallower than the ST-G, the ST-MAX is conspicuously longer from front to back and from heel to toe. That extra length means extra carbon (40% more) in the crown and sole which saved a decent amount of weight.

When manufacturers earn themselves a little discretionary weight, they like to reposition it low and back in the head to give the club a higher MoI (the ST-MAX 230’s is the highest the company has ever made, in fact) making it more stable. With the extra carbon, Mizuno saved a whopping 54 grams. That amount of weight at the back of your driver is definitely going to make it easier for you to drive the ball straighter.

The carbon sole and crown are familiar from previous ST drivers of course, as is the CorTech Chamber – a dense piece of stainless steel encased in TPU, and positioned in the sole toward the clubface. Its properties and position allow the face to flex a little more, give a little extra speed, and soften the sound. The ST-MAX 230’s CorTech Chamber is a little bigger than previous CorTech Chambers which, in turn, gives it a little more ball speed still and a slightly softer sound.

Mizuno ST-MAX 230

While the backweight makes the ST-MAX 230 extremely stable which appeals to high-handicappers, its face ensures ballspeeds remain high enough to keep better golfers happy. Made from the same Beta Rich Ti-LFS (Lighter, Faster, Stronger) material that debuted in the ST-G, the face gives 1.5mph more speed than the SAT 2041 Beta Ti found on the ST-X and ST-Z, according to Mizuno.
The lighter head enabled Mizuno to put longer shafts (45 ¾”) in the ST-MAX 230 which should give you a little extra clubhead speed. And the Quick Switch hosel gives you four degrees of adjustability.

Lofts – 9.5˚ (RH and LH), 10.5˚, 12˚ (RH only)
Shafts – UST LIN-Q Red, UST Helium NanoCore 4F1, Mitsubishi Kai’li Blue, Project X HZRDUS Smoke Green.
See also ST-MAX Fairways and hybrids


Colorado AvidGolfer Magazine is the state’s leading resource for golf and the lifestyle that surrounds it, publishing eight issues annually and proudly delivering daily content via

Tony Dear is a former teaching professional and First Tee coach, now a freelance writer/author living in Bellingham, WA. He can be reached at [email protected] 

Follow us on Twitter, Facebook and Instagram