More than ever, golfers around the world are interested in testing longer-length drivers. If you’re one of these golfers, the biggest question is, “How do I get started?” Because as most serious golfers know, you can’t just switch to a longer shaft and expect better results. Some testing and tweaking will be in order.

TPT Head of Performance Jon Sinclair has been extensively testing longer-length TPT shafts with his Tour players and amateur golfers over the last month. We wanted to share those initial findings with our TPT Authorized Fitters and anyone who is interested in trying a longer-length driver.

#1: Pay Attention To Head Weight

The first thing most golfers will notice when they switch to a longer-length driver shaft — particularly when they try the maximum legal length of 48 inches – is that the driver will feel much heavier.

This is not due to the additional shaft length, as an additional two or three inches of golf shaft doesn’t add a meaningful amount of weight to a golf club. It does dramatically increase the club’s swing weight, however, which is a measure of the balance point of a club and how heavy it “feels” during the swing.

Most golfers who are fit for a TPT shaft perform best with a swing weight of D5 and a length of 45 inches. If we simply add a 48-inch shaft to that same club (an extra 3 inches), we would see the swing weight increase approximately 15 points approaching the F range.

While we want to keep the head weight as heavy as possible to maximize the potential for ball speed – remember that with all other things being equal, heavier club heads will create more ball speed than lighter club heads – we do not want the club head to be so heavy that it causes swing speed to decrease. For this reason, golfers who are testing longer drivers need to have access to lighter head weights and back weights.

#2: MOI Matters

The reason you would think a golfer could swing a longer club faster is that if you get the club head farther away from the center of rotation it should move faster. In theory, this is correct.

What is also correct is that the moment of inertia (MOI) of the club will increase as we increase the length of the club (shown in the graph as A to A1). This is why it’s harder to swing a longer-length driver than a shorter-length driver. Golfers must apply more torque to swing a longer club.

#3 Focus on Ball Speed, Not Swing Speed

In Sinclair’s testing, there has been a point of diminishing return when increasing driver length for most golfers. One example is a golfer who swung a 48-inch driver slower than a 45-inch driver. Both drivers had the same head weight, but the 45-inch driver had a D5 swing weight and the 48-inch driver had an E9 swing weight. This increased the MOI of the 48-inch driver, which is why the player could not swing it as fast as the 45-inch driver. Therefore, the 45-inch driver generated more ball speed. Clearly, for this golfer, the 45-inch shaft makes more sense for distance and dispersion consistency.

In every fitting, we need to focus on identifying the length of driver that allows golfers to produce the most ball speed, and for some golfers, this could actually result in them playing a shorter-length driver.

The hard and fast rule in club fitting is that every additional 1 mph of ball speed is going to create about 2.5 yards of additional carry distance. So, if you’re adding 4 mph of ball speed with a longer-length driver, that can translate to a 10-yard increase in carry distance, which is game-changing for any golfer.

Keep in mind that club head speed and ball speed closely correlate when we’re testing two clubs of the same length and head weight and contact points are the same. But when we’re searching for more distance with longer-length clubs, this correlation can change. A 48-inch driver with a lighter head weight may allow a golfer to increase their swing speed 4-5 mph, but we may also see a decrease of 4-5 mph in ball speed due to the lighter head weight.

To maximize efficiency in fittings, which is an important goal because golfers can only make so many driver swings in one day, what Sinclair recommends is that golfers go up in length 0.5 inches at a time to find the length that offers the most ball speed.

As length is increased, fitters must keep an eye on a golfer’s ability to create center strikes and keep the club head speed up. Keeping this speed up may require that a fitter removes weight from the club head, but as we discussed earlier this has the drawback of removing potential ball speed. The good news is that there is another way.

#4: Back Weighting

In back weighting the shaft with either a heavier grip or a weight installed in the butt of the grip, we are in fact making the club heavier. But the club will actually feel lighter to the golfer because the back weighting lowers the swing weight of the club, thus decreasing its MOI. For this reason, back weighting can allow a golfer to have their cake a eat it, too. They can keep their head weight the same to maximize ball speed while at the same time making the club easier to swing.

Before we start removing weight from the club head or using back weighting, however, we need to find out how much swing weight a player can handle without affecting their overall performance. The object is to get players farther down the fairway without losing their ability to hit fairways. This is the give and take we must always monitor with longer-length clubs.

#5: Yes, Dispersion Will Be Affected

If you’ve ever played golf with someone with a very slow swing speed, you’ll notice that the ball tends to fly relatively straight and not curve that much. This has to do with the physics of impact.

Any time we’re increasing ball speed, we’re also increasing the potential severity of offline shots: not just hooks and slices but pushes and pulls as well. It’s up to every golfer to determine exactly how much of a trade they’re willing to make for the potential to hit longer drives.

The good news is that there are golfers in the world who hit 45.5-inch drivers farther and straighter than 44.5-inch drivers and vice versa. This has to do with their individual preferences and mechanics. What we’ll be learning over the next year or so is if we can help golfers hit 46-, 47-, or even 48-inch drivers almost as straight as shorter drivers.

TPT shafts are known for their tight dispersion, which allows golfers to swing more aggressively. This is what makes it possible for golfers to swing faster with a TPT shaft no matter what length they need.

#6: Pay Attention To Where Head Weight Is Positioned

The last thing to note about head weight is that it may need to be positioned in a different part of the head than what’s typical for a golfer. A longer shaft is going to droop and deflect more than a shorter shaft, which could mean a different CG position to help a golfer square up the face. Thank goodness for adjustable drivers!

#7: Watch Out For Higher Launch And Higher Spin

Longer-length drivers are likely to create a higher launch angle and a higher spin rate. This has to do with several factors. The first reason is that increasing club speed can also increase spin. The second reason is that longer-length shafts play “softer” and can add more dynamic loft, which in turn creates a higher launch and a higher spin rate. Back weighting a shaft can help alleviate some of these issues.

For all of these reasons, golfers testing longer-length drivers with their fitter will likely want to also test lower-lofted heads and different stiffnesses in shafts to maximize their performance. Sinclair has actually seen players perform better with softer shafts in longer drivers, which once again shows the importance of testing different shaft models as the length is adjusted.

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