QA Green Speeds at Augusta

By Frank ThomasApril 4, 2007, 4:00 pm
Editor's Note: This is the latest in a weekly Q&A feature from The Golf Channel's Chief Technical Advisor Frank Thomas. To submit a question for possible use in this column, email
Dear Frank:
With The Masters coming up this week I was wondering about green speed and how this is determined for this championship. The greens are always so slick and scary looking!! I read that you were involved with the Stimpmeter and thought that maybe you could answer my question.
Thank you,

Yes, I was involved with the Stimpmeter. In 1976 I re-designed a device that had been developed in 1935 by Eddie Stimpson but rejected by the USGA at that time. The original was not very consistent in its readings. I first tried out two very elaborate designs of my own, which turned out to be good but clumsy, and dependent on the skill of the operator. I then took Eddie's concept and redesigned it, and since the conception was his I called it the Stimpmeter, which was what he had called his.
A ball is positioned in a slot at the top end of a 'V'- grooved aluminum beam. The beam is slowly raised until gravity pulls the ball out of the slot and it runs down the groove onto the green. The distance it rolls from the end of the Stimpmeter on a flat portion of the green is the speed of the green, measured in feet. It is very consistent, simple, and now used around the world.
In 1977, I asked our agronomists at the USGA to measure greens during their visits to various clubs. They returned data that I analyzed to try to develop some standards for green speeds. This proved to be 66 for everyday play at golf courses, and 8' 6'' for average competition play. For championship play in 1977, 10' 6' was considered fast. To reach that speed, we had to double or even triple cut the greens; we made sure that if the greens were undulating we would keep the speed somewhat slower.
In 1998, at the Olympic Club in San Francisco during the US Open the fairways were running at 6' 6'. Not only had significant agronomic changes taken place, but mowers designed for greens were being used on the fairways. Today, if you want to roll the greens and really shave them down, you can get them as fast as 15 feet, as was the case at Bethpage Black on the Sunday of the Open in 2002.
The green speed at Augusta National is a secret, but whatever it is it should be fair and very much dependent on the undulations of the green. You never want to have the ball accelerating past the hole from any direction; if it does, then either the hole location is inappropriate or the speed is too fast. A ball should be able to stop close to the hole when putted from almost any location on the green. This does not mean it should be easy to do, but it should be possible. With the above in mind, there is quite a responsibility on the shoulders of the individual in charge of dictating green speed and hole locations. I suspect the greens for the Masters will be close to 12 feet.
For more on the Stimpmeter please click here.
Hope this helps,
Thank you for sharing your experience in a weekly column. I look forward to reading it every week.
I have a question regarding moment of inertia and I haven't been able to find the answer. What, if any, effect does the length of the club and the loft of the club head have on MOI?
Thanks, Frank,

The MOI (Moment of Inertia) is a measure of the resistance to angular acceleration -- in other words, twisting. (Click here for an easy explanation of MOI).
You can experience this by holding two weights (20 lbs) close to your body, one in each hand, and twist your torso quickly through about 180 degrees. Now stretch your arms out and try to twist again. This time it will be more difficult to twist quickly, and, once you get started twisting it will be more difficult to slow down. What you have done by moving the weights away from your body (the axis of rotation), is to increase the MOI.
This is why cavity back clubs have a higher MOI than blades and are more forgiving of mis-hits -- because they dont twist as easily. The weight has been moved to the outside perimeter of the head. Similarly, in hollow metal wood clubs, all the weight is distributed into the shell, so they also have a high MOI. The result is that the club head doesnt twist easily on off-center impacts, and so imperfect shots fly straighter.
Only now can I answer your specific question. If you are talking about the MOI of the head itself, then changing the length of the club or the loft will have no effect on the MOI of the head.
You should, however, also understand that the measurement of MOI is based on the axis of rotation, which in the case of the club head alone is its center of gravity. If we try to measure the MOI of the club as a whole -- the shaft, grip and head -- and the axis of rotation is at the grip end, then the length of the club makes a big difference.
Try to hold a club at the head end and swing the grip. Now reverse this and hold it at the grip end and swing the head. It will be much easier to swing the grip than to swing the head. This is because the head is heavier than the grip and at some distance away from the axis of rotation (your hands). The MOI is different. Thus, by changing the length of the club you are also changing the MOI of the club as a whole -- but not changing the MOI of the head itself.
I hope this helps you better understand MOI, which every body talks about but now you understand.
Your following comment really got my attention:
DON'T add weight to the butt end of the club to achieve a certain swingweight. This is done sometimes in club fitting to make the customer happy, but it does absolutely nothing for you.
I have been reading a lot about MOI fitting, and each article seems to indicate adding weight to the butt is the magic fix. Grip manufacturers are even selling grips with a special feature for adding weight. Whats the real story on MOI fitting?

Matching by MOI of the club is normally done by making a measurement about a specific axis somewhere close to the grip end of the club. If this is based on the last foot or so before impact, the point would be about 4 inches above the grip end, as this is the instant center of rotation in this segment of the swing.
Adding weight to the grip to change the MOI of a club is not very effective. This should be done by changing the weight of the head or lengthening the club.
Adding weight to the grip end is the equivalent of wearing a heavier glove or even a wrist watch. This does change the MOI of the first lever -- i.e. the arms, with the attached hands -- but does nothing for the MOI of the club if we are placing the axis of rotation in the vicinity of the hands.
If adding weight to the grip really worked wonders, dont you think after 400 years of trial and error we would have discovered this before now?
My position is, if it feels good, try it. Adding weight to the grip end will certainly increase the hand mass and the MOI of the first lever. But since the club head path changes its radius of rotation throughout the downswing, I dont know the value of this particular form of balancing for MOI, since it is wholly dependent upon what axis of rotation you are using as a basis for measurement.
In general, I do not see how butt weighting can be the magic fix, or how it is going to have a significant effect on performance.
Click to purchase the Frog PutterFrank Thomas, inventor of the graphite shaft, is founder of Frankly Golf, a company dedicated to Helping Golfers. Frank is Chief Technical Advisor to The Golf Channel and Golf Digest. He served as Technical Director of the USGA for 26 years and directed the development of the GHIN System and introduced the Stimpmeter to the world of golf. To email a question for possible use in an upcoming Let's Be Frank column, please email
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Koepka (wrist) likely out until the Masters

By Ryan LavnerJanuary 19, 2018, 9:08 pm

Defending U.S. Open champion Brooks Koepka is expected to miss at least the next two months because of a torn tendon in his left wrist.

Koepka, who suffered a partially torn Extensor Carpi Ulnaris (ECU), is hoping to return in time for the Masters.

In a statement released by his management company, Koepka said that doctors are unsure when the injury occurred but that he first felt discomfort at the Hero World Challenge, where he finished last in the 18-man event. Playing through pain, he also finished last at the Tournament of Champions, after which he underwent a second MRI that revealed the tear.

Koepka is expected to miss the next eight to 12 weeks.

“I am frustrated that I will now not be able to play my intended schedule,” Koepka said. “But I am confident in my doctors and in the treatment they have prescribed, and I look forward to teeing it up at the Masters. … I look forward to a quick and successful recovery.”

Prior to the injury, Koepka won the Dunlop Phoenix and cracked the top 10 in the world ranking. 

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Cut Line: Color Rory unafraid of the Ryder Cup

By Rex HoggardJanuary 19, 2018, 7:09 pm

In this week’s edition, Rory McIlroy gets things rolling with some early Ryder Cup banter, Dustin Johnson changes his tune on a possible golf ball roll-back, and the PGA Tour rolls ahead with integrity training.

Made Cut

Paris or bust. Rory McIlroy, who made his 2018 debut this week on the European Tour, can be one of the game’s most affable athletes. He can also be pointed, particularly when discussing the Ryder Cup.

Asked this week in Abu Dhabi about the U.S. team, which won the last Ryder Cup and appears to be rejuvenated by a collection of new players, McIlroy didn’t disappoint.

“If you look at Hazeltine and how they set the course up – big, wide fairways, no rough, pins in the middle of greens – it wasn’t set up for the way the Europeans like to play,” McIlroy said. “I think Paris will be a completely different kettle of fish, so different.”

McIlroy has come by his confidence honestly, having won three of the four Ryder Cups he’s played, so it’s understandable if he doesn't feel like an underdog heaidng to Paris.

“The Americans have obviously been buoyant about their chances, but it’s never as easy as that,” he said. “The Ryder Cup is always close. It always comes down to a few key moments, and it will be no different in Paris. I think we’ll have a great team and it definitely won’t be as easy as they think it’s going to be.”

September can’t get here quick enough.

Mr. Spieth goes to Ponte Vedra Beach. The Tour announced this year’s player advisory council, the 16-member group that works with the circuit’s policy board to govern.

There were no real surprises to the PAC, but news that Jordan Spieth had been selected to run for council chair is interesting. Spieth, who is running against Billy Hurley III and would ascend to the policy board next year if he wins the election, served on the PAC last year and would make a fine addition to the policy board, but it is somewhat out of character for a marquee player.

In recent years, top players like Spieth have largely avoided the distractions that come with the PAC and policy board. Of course, we’ve also learned in recent years that Spieth is not your typical superstar.

Made Cut-Did Not Finish (MDF)

On second thought. In December at the Hero World Challenge, Dustin Johnson was asked about a possible golf ball roll-back, which has become an increasingly popular notion in recent years.

“I don't mind seeing every other professional sport. They play with one ball. All the pros play with the same ball,” he said in the Bahamas. “I think there should be some kind of an advantage for guys who work on hitting it far and getting that speed that's needed, so having a ball, like the same ball that everyone plays, there's going to be, you're going to have more of an advantage.”

The world No. 1 appeared to dial back that take this week in Abu Dhabi, telling BBC Sport, “It's not like we are dominating golf courses. When was the last time you saw someone make the game too easy?”

Maybe it didn’t feel that way, but DJ’s eight-stroke romp two weeks ago at the Sentry Tournament of Champions certainly looked pretty easy.

Long odds. I had a chance to watch the Tour’s 15-minute integrity training video that players have been required view and came away with a mixture of confusion and concern.

The majority of the video, which includes a Q&A element, focuses on how to avoid match fixing. Although the circuit has made it clear there is no indication of current match fixing, it’s obviously something to keep an eye on.

The other element that’s worth pointing out is that although the Tour may be taking the new program seriously, some players are not.

“My agent watched [the training video] for me,” said one Tour pro last week at the Sony Open.

Missed Cut

Groundhog Day. To be fair, no one expected Patton Kizzire and James Hahn to need six playoff holes to decide last week’s Sony Open, but the episode does show why variety is the spice of life.

After finishing 72 holes tied at 17 under, Kizzire and Hahn played the 18th hole again and again and again and again. In total, the duo played the par-5 closing hole at Waialae Country Club five times (including in regulation play) on Sunday.

It’s worth noting that the playoff finally ended with Kizzire’s par at the sixth extra hole, which was the par-3 17th. Waialae’s 18th is a fine golf hole, but in this case familiarity really did breed contempt.

Tweet of the week:

It was a common theme last Saturday on Oahu after an island-wide text alert was issued warning of an inbound ballistic missile and advising citizens to “seek immediate shelter.”

The alert turned out to be a mistake, someone pushed the wrong button during a shift change, but for many, like Peterson, it was a serious lesson in perspective.

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Watch: McIlroy gives Fleetwood a birthday cake

By Golf Channel DigitalJanuary 19, 2018, 2:58 pm

Tommy Fleetwood turned 27 on Friday. He celebrated with some good golf – a 4-under 68 in Abu Dhabi, leaving him only two shots back in his title defense – and a birthday cake, courtesy of Rory Mcllroy.

While giving a post-round interview, Fleetwood was surprised to see McIlroy approaching with a cake in hand.

“I actually baked this before we teed off,” McIlroy joked.

Fleetwood blew out the three candles – “three wishes!” – and offered McIlroy a slice.  

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DJ shoots 64 to surge up leaderboard in Abu Dhabi

By Ryan LavnerJanuary 19, 2018, 1:48 pm

Dustin Johnson stood out among a star-studded three-ball that combined to shoot 18 under par with just one bogey Friday at the Abu Dhabi HSBC Championship.

Shaking off a sloppy first round at Abu Dhabi Golf Club, Johnson matched the low round of the day with a 64 that put him within four shots of Thomas Pieters’ lead.

“I did everything really well,” Johnson said. “It was a pretty easy 64.”

Johnson made four bogeys during an even-par 72 on Thursday and needed a solid round Friday to make the cut. Before long, he was closer to the lead than the cut line, making birdie on three of the last four holes and setting the pace in a group that also included good rounds from Rory McIlroy (66) and Tommy Fleetwood (68).

“Everyone was hitting good shots,” McIlroy said. “That’s all we were seeing, and it’s nice when you play in a group like that. You feed off one another.” 

Full-field scores from the Abu Dhabi HSBC Championship

Coming off a blowout victory at Kapalua, Johnson is searching for his first regular European Tour title. He tied for second at this event a year ago.

Johnson’s second-round 64 equaled the low round of the day (Jorge Campillo and Branden Grace). 

“It was just really solid all day long,” Johnson said. “Hit a lot of great shots, had a lot of looks at birdies, which is what I need to do over the next two days if I want to have a chance to win on Sunday.”