Unofficial Review: Dumina AutoFlex SF505X Driver Shaft

[edingc 8,464]

Unofficial Review: Dumina AutoFlex SF505X Driver Shaft

Long, cold winters without playing golf are dangerous for the wallet.

I try to be a frugal golfer. I built my last two irons sets to save some cash, play at an affordable, municipal-style course and balk at spending $60/hour for simulator practice in the offseason. But, after seeing launch monitor numbers on YouTube and tour validation with Adam Scott, the mystique of Dumina’s AutoFlex became too hard to pass up.

I am not a particularly great driver of the golf ball. I struggled with an inside takeaway and a steep, over-the-top wipe at the golf ball for most of my golfing life. As you can imagine, I did not have good results with the big stick.

I’ve been fortunate enough to have tested two drivers for the MyGolfSpy Forums now. Both times I fit into a stout, low-launch/low-spin shaft to offset my delivery. After working with my coach for the past 18 months, I’ve made some good progress with my driver swing. This winter, I switched to a nine degree Callaway Mavrik head with an x-stiff Aldila Rogue White 60 shaft. I gained a bit of launch without adding spin with this combination. I am hitting the driver better and further than ever before based on my FlightScope Mevo numbers.

My Mevo numbers at the heated winter range have stayed between 110-117 MPH club speed and 158-165 MPH ball speed. I had the opportunity to hit range balls outdoors once last week when we had weather in the low 40s. After 15 shots my averages looked like the following:

Ball Speed	Club Speed	Smash	Carry	Launch	Spin	Height (ft)	Time
160.2	109.2	1.47	260	12.5	2,640	108	6.9

On course, I am too tentative and usually do not reach the same level of speed as I do on the range. That said, I had a handful of nice drives during my first round of the season this past weekend:

My goal with the driver is to keep the ball in play and not cost myself penalty strokes. I am still working on the confidence to swing faster knowing I've improved.

My apprehension to swinging faster (which is definitely a mental issue) is one of the factors driving me to try the AutoFlex. The shaft could be a game changer if I can get a few more MPH club head speed without feeling like I’m swinging harder/faster.

Fitting and Ordering Process

Limited information is available online about what a “proper fit” is with the AutoFlex. As many of the TXG YouTube videos have highlighted, there are specific headweight and swingweight considerations to account for when determining playing length, head choice, etc.

A lengthy thread over at GolfWRX is devoted to the AutoFlex, but I found the best information in a Facebook group dedicated to players/users of the shaft. There, I found some “real world” advice from people who had tried and failed/succeeded in using the AutoFlex. For my build, I was targeting a 45.75” finished length and a swingweight between D1 and D2. These specifications are recommended by the manufacturer and also the members of the group.

Before placing my order, I made a post on the group and received helpful confirmation of my plans from a knowledgeable member. Although not required, I did order the shaft from one of the professional fitters in the group. His price was the best I found. The shaft came cut to my specifications with a Callaway adapter installed within three days. I installed a Lamkin Sonar Tour grip to match my other clubs once I received the shaft.

I am not aware of an AutoFlex available to try locally.

My Setup

I replaced the stock five gram Mavrik weight with an aftermarket weight weighing two grams. Many people have chosen to go with a heavier grip to “trick” the swingweight scale. However, it seemed like the most successful players had opted for lighter head weights instead.

 

Rogue White 60X
Length	45.25” (45.5” to very end of grip)
Headweight	192 grams
Swingweight	D2.5

 

AutoFlex SF505X
Length	45.75” (46” to very end of grip)
Headweight	189 grams
Swingweight	D1.5

The Facebook commenter mentioned I may need to loft down the Mavrik head to eight degrees. I currently play at the stock loft.

First Impressions

From a looks standpoint, the AutoFlex is gorgeous. Yes, the hot pink may not be for everyone. I love that it stands out in the bag. The “black” color is not flat black, it is more of a pearly green-black at close inspection. Very sharp!

I know of no other shaft that arrives in its own protective sheath. A nice touch.

The feels from the initial waggle were as advertised. Imagine taking a club head and attaching it to a fishing pole. There is plenty of waggle/movement from the head. But it does not feel that way when swinging. It will be intriguing to hit a ball and see how it feels at impact.

I completed an initial test by taking three swings without a ball each with the Rogue White and AutoFlex. After quickly warming up, I measured my club speed with my Sports Sensors radar.

• My three swings with the Rogue White recorded at 110 MPH, 111 MPH and 113 MPH.
• My three swings with the AutoFlex recorded at 115 MPH, 114 MPH and 116 MPH.

Keep in mind the AutoFlex plays 1/2” longer than the Rogue White. I’m not willing to chalk up the speed gains in this brief test to anything more than length (yet).

I expect my driving range to open for the season sometime in the next two weeks. I will be able to gather more data and feedback at that time.

Is a driver shaft worth $800?

Probably not, although I’m keeping an open mind.

I would be ecstatic if the AutoFlex magically added 3-5 MPH club speed and the 4-7 MPH ball speed that should accompany. On a well-struck shot, that would be a quantifiable distance gain. However, I’m starting without any high expectations.

Part of what I enjoy about golf is trying out new equipment, so much so that my constant swaps are most likely detrimental to my scores. I’m not usually one to usually experience FOMO, but in this case I got wrapped up in the allure of this mysterious shaft.

And, at the end of the day, I still expect resale to be reasonable. Always need to have a backup plan. 

[cksurfdude 8,346]

So the "Auto Flex" name made me think of UniFlex shafts in the not too distant past ... is the general idea (without looking at their website) that a given model is supposed to "adapt" to varying swing speeds, swing tempos, transitions/deliveries, ...??

[edingc 8,464]

12 hours ago, cksurfdude said:

So the "Auto Flex" name made me think of UniFlex shafts in the not too distant past ... is the general idea (without looking at their website) that a given model is supposed to "adapt" to varying swing speeds, swing tempos, transitions/deliveries, ...??

TXG's initial review of the AutoFlex pretty much says that is the general idea. The company calls it "Korean Hidden Technology," but does not go into specifics about how the shaft works or is constructed (so much so that they apparently have opted not to file a patent for the technology lest it be imitated in some way).

Someone over on WRX sent the shaft off to be EI profiled, and as a static shaft it is most similar to very light "ladies" shafts.

The actual "fitting" is kind of a moving target. Initially, the SF505X was said to be for swing speeds upwards of 125 MPH, but recent charts (like the one I took from the English version of the AutoFlex website), recommend the strongest of swingers use the SF505XX.

[cksurfdude 8,346]

^ Interesting, thx!

[yungkory 10,338]

Wow, I can't believe you bought one. I no longer feel so bougie for my DF 2.1 purchase, so thanks for that! If it doesn't work, at least people who know about the shaft will know you're a baller.

[edingc 8,464]

I spent some more time with the AutoFlex outside yesterday swinging without a ball. I hit 124 MPH on the radar once, and saw several 122 MPH readings without feeling like I was swinging uncontrolled/"out of my shoes."

If I remember correctly, the highest no ball reading I saw with a driver throughout the winter was 126 MPH once. Speed has actually been trending slightly downward over the past few weeks, and I hadn't seen anything that close to 122 MPH in a while. 

Looking at our weather report, my range might actually open this week yet! Fingers crossed.

[PMookie 13,174]

I had no idea their shafts were that light. Interesting! Looking forward to following to see how it works for you!

[juspoole 1,881]

Looking forward to following!  I'm wondering how many of these we will see on tour.  Adam Scott was the first, but I am sure will not be the last.  

Do you have a way that you might be able to determine if dispersion is the same or improved?  

[edingc 8,464]

8 minutes ago, juspoole said:

Do you have a way that you might be able to determine if dispersion is the same or improved?  

I hit a pretty consistent 40-45 percent of fairways over the past two seasons, but that includes irons off tee/etc. Even with Arccos I can't say I have a great way to track dispersion. Might need to rent some time on my coach's Trackman just to compare the two setups on a single day type of thing.

[B.Boston 10,527]

Well this should be an interesting follow.  Still a lot of mystery behind the Autoflex.  

I'm interested to see if your ball speed goes up even if swing speed goes up with the lighter head.  Hopefully that forecast holds and you can hit some balls outside this week.

[edingc 8,464]

2 hours ago, B.Boston said:

Well this should be an interesting follow.  Still a lot of mystery behind the Autoflex.  

I'm interested to see if your ball speed goes up even if swing speed goes up with the lighter head.  Hopefully that forecast holds and you can hit some balls outside this week.

Regarding ball speed vs. head weight, I found some pretty interesting testing done at this blog: http://0to300golf.blogspot.com/2019/04/testing-driver-head-weights-part-2.html

They had best results when matching a lighter head with a reasonable swingweight (D2), which is what the Dumina chart implies.

I went back and watched the original TXG video last night and Matt seemed to have significantly more success with his Mavrik SZ head than the G410LST, which was a lot heavier than the Mavrik. My hypothesis is that the AutoFlex needs a truly lighter swingweight and not a "tricked" swingweight with a heavy grip or counterbalance weight. It seems the most successful people I've seen play a lighter head. Some people on the Facebook forum have had good results with XXIO drivers, and Gabe Gallucci on YouTube had the most success with lighter weights in his Mavrik SZ as well, which brought the headweight down into the 180s.

I could drop the 2 gram weight and get down below D1 if I wanted to give that a shot as well. Anything "lighter" on the scale would mean shaving more off of the shaft, which I'd really rather not do.

[B.Boston 10,527]

5 minutes ago, edingc said:

Regarding ball speed vs. head weight, I found some pretty interesting testing done at this blog: http://0to300golf.blogspot.com/2019/04/testing-driver-head-weights-part-2.html

They had best results when matching a lighter head with a reasonable swingweight (D2), which is what the Dumina chart implies.

I went back and watched the original TXG video last night and Matt seemed to have significantly more success with his Mavrik SZ head than the G410LST, which was a lot heavier than the Mavrik. My hypothesis is that the AutoFlex needs a truly lighter swingweight and not a "tricked" swingweight with a heavy grip or counterbalance weight. It seems the most successful people I've seen play a lighter head. Some people on the Facebook forum have had good results with XXIO drivers, and Gabe Gallucci on YouTube had the most success with lighter weights in his Mavrik SZ as well, which brought the headweight down into the 180s.

I could drop the 2 gram weight and get down below D1 if I wanted to give that a shot as well. Anything "lighter" on the scale would mean shaving more off of the shaft, which I'd really rather not do.

I think the TXG boys also said that heavier head weight has become less of an advantage now that I think about it. OEMs are getting better with face tech to keep ball speeds up. 
 

I have to agree with you that it’s a combo of the swing and real weight that seems to make the autoflex work. 

[revkev 22,956]

I can’t wait to see your range and then on course results!

Thanks for doing this test.


Sent from my iPhone using MyGolfSpy

[edingc 8,464]

Quite an interesting first day on the range with the AutoFlex. A very whip-like feel everywhere but at impact. Such an odd shaft.

Not surprisingly, the AutoFlex didn't magically make me drive the ball like Bryson. Even though the shaft is only 1/2" longer than the Rogue White, it took a bit to adjust to the longer length. I tend to struggle with balance and setup, getting too bent from the hips at address. That kind of bent-over setup can cause me to stand up through impact, and it gets worse the longer the club. You'll see me try to get taller at address as the shots go on, and that's something I need to work on if my driver is going to improve.

I'm sure setup accounted for some of this today, but I didn't hit the center of the club face much. I heeled a lot of shots, hit a lot of others low in the face and had one or two that almost missed the face altogether. It seemed a bit hard to find a groove with the AutoFlex. But, it was my second range session of the year and tough to tell for sure what was the cause.

Numbers-wise, I didn't see much change. Over 19 shots, the AutoFlex was comparable to my Rogue White numbers from Friday (differences highlighted):

Ball Speed	Club Speed	Smash	Carry	Launch	Spin	Height (ft)	Time
158.8 (-1.4)	111.5 (+2.3)	1.42 (-0.05)	256.5 (-3.5)	N/A	2,540 (-100)	N/A	N/A

The numbers are from two different ranges and two different mixes of range balls. The difference in elevations between ranges mess with the Mevo readings for launch, height and time so I've removed them. I'm not sure how much faith to put in these numbers this early.

The low-faced hits has me thinking the AutoFlex is deflecting a lot coming into impact. The majority of my shots today launched very high.  The next time out I will loft the Mavrik down to eight degrees. Also, near the end of the session I switched to my tallest tee (2.5" above ground, 4" total), and that helped center the ball vertically on the face.

Quite a few balls visibly had too much spin, but I would guess hitting them low on the head was the cause of that. I middled the last shot in the video and crushed it.

I can't say the AutoFlex was any better or worse than the Rogue White in regards to dispersion. My good shots are slight draws, awful shots are duck hooks or high and right. Those misses have been consistent all winter through four different driver/shaft combinations.

[GolfSpy MPR 10,611]

Looking forward to your continued updates. I think I can speak for a lot of us that we had hoped to read about a miraculous improvement.

[edingc 8,464]

37 minutes ago, GolfSpy MPR said:

Looking forward to your continued updates. I think I can speak for a lot of us that we had hoped to read about a miraculous improvement.

Certainly always looking for magic in a bottle, so to speak.

In rewatching my clip, I did notice the majority of my best shots came near the end of the bucket after making the tee change and after getting more used to the feel of the shaft. That has me excited to get out there again, hopefully Friday. I have a round scheduled for Saturday morning again, too. The AutoFlex will get put through its paces.

Your comment on "miraculous improvement" does lead me down a rabbit hole. What kind of changes do I need to see to somehow say an $800 shaft is worth the price tag? How can I quantify that? With something like my L.A.B. putter, I saw immediate changes to my scoring and distance control. In cycling through three or four drivers in two years, I can't say I've gotten a ton better outside of any improvements I've made from lessons and good 'ol practice.

One thought that did cross my mind is how I react to a lighter shaft later in rounds. During my first round of the season I drove the ball really well on the front nine. But, as I tired, the driver started to get very squirrelly on the back nine. Will switching to a shaft that is something like 10 grams lighter than the Rogue White help out there?

[Chip Strokes 3,719]

like i told you in the other thread, i had the opportunity to hit the 505XX with a sim2 head. 

like you, i had trouble centering the ball with the shaft playing 1.5” longer than my gamer. my sample size was small, only 5 or 6 shots, but i’m cautiously optimistic about what the shaft can do. 

my swing speed was up 2-3mph over what i was seeing with my gamer that day. i actually saw 140+ with the autoflex. and ball speed retention on poor strikes was awesome. i was missing high and toe side and was still seeing ball speeds in the high 180s and low 190s. 

the few swings i took launched the ball to the moon. now that could be strike location as much as anything else, but it was half a dozen consecutive shots that went way too high to even be considered playable. they carried decently, but that was in perfect conditions on a sim. on the course 170+ feet in the air with wind i likely would’ve seen that ball come up 40+ yards short. 

like i said...too small a sample size to make a definitive statement but extremely interesting none the less. 

i can’t wait to see your thoughts as you continue to try it out. 

[edingc 8,464]

I was able to get out on the range yesterday afternoon after my lesson. Following a lesson is likely the worst time to evaluate a new club/shaft, but I was eager to hit the AutoFlex again.

The session went much the same way as my first, with an impact pattern all over the face. My average club speed shot up to 113 (warm and loose from the lesson), but my efficiency was terrible (1.4) with an average ball speed of 158.3. Disappointing numbers. I know range balls vary and don't produce the same ball speed as a premium ball. But, I've been tracking my driver all winter and a range ball speed of 158.3 isn't above my average.

Heel hits filled the majority of both early sessions. Low heel used to be my miss, but I haven't seen consistent contact there in quite some time. 

To be fair to the AutoFlex, the Facebook users group implies very few people will have "plug and play" success. Many members mentioned they likely wouldn't have chosen the AutoFlex based on a single fitting or testing session. Several experimented with different weights and hosel settings before finding a working combination.

I re-installed the stock five gram weight in the Mavrik last night. The extra three grams moved the swingweight from D1.5 to D2.5. I am now above the range recommended by Dumina, but back to what I had with the stock Aldila Rogue White.

I was back out on the range during lunch today and had much better results with the stock weight installed. I also switched back to my lower tee. I still missed a few low heel, and a couple high middle/toe, but I hit a ton more out of the near middle than I did on the first two days.

Getting the contact location squared away made the AutoFlex shine. I averaged 112 MPH swing speed and 162.7 MPH ball speed over my 38 shots. 

I am finding you cannot rush with the AutoFlex. I found the most success feeling a long and smooth takeaway before allowing myself to be violent through the ball. My worst shots came from ripping the club back too fast on the back swing.

I hit two blocks of about 20 drivers each. The first block was good, but the second block was amazing. Over my last six shots I averaged 165 MPH ball speed (max 167.9) and 111.6 MPH club speed (max 113.9). Launch and spin fell in acceptable ranges, and I was right around 90-100 feet peak height.

[cksurfdude 8,346]

Wow! Looks like your determination is paying off

[Thin2win 2,092]

Glad it is working for you so far. any more testing with it lately?