Clubhead & Ball Speeds Are Correct...but Yardages Are Hugely Inflated...

[Morini]

Once more, just to be clear. The skytrak is accurate. There is no inflation. When spin drops due to hitting off a mat, the ball carries further. Just physics. If you don't believe me just paste your ball data into flight scope trajectory optimizer. https://flightscope.com/products/trajectory-optimizer/

[Morini]

No, they are not over inflated. It accurately reads your low spin. You would have the exact same result with a Quad or TM4 ... or if you opened your garage door and measured where the ball landed down the street. Hit off a short tee to rule out mat as cause of slow spin.

[Bubba22]

Try hitting some short teed iron shots as mentioned above by Fhacker.

[Rogala]

OK, just hit some balls with:

a) the feet off the metal case, and the base of the unit on a support mat next to the hitting mat, therefore the same height as the hitting mat (or at least within 1/8"), and
b) the ball logo pointed at the camera.

RPM numbers are very different than earlier, with an average backspin number of around 4,000 RPMs...again lower than I expected...but this time all the calculated carry and roll yardages made perfect sense vs. my IRL experience.

The data attached below were from 10 shots off my hitting mat mounted on a plywood base (with a built-in gelpad in the hitting area to mimic going down into the turf with the clubhead) and hit with a 34 degree 7-iron. I deleted 4 other shots from the data set as I knew (via contact feel and sound) that I hit them either slightly fat or slightly thin. Shot #5 in the data set also felt like a slightly wonky one, but I left it in as it is representative of the low RPM numbers I was getting yesterday, even though the distance numbers seemed to make logical sense in the context of my other shots.

I used my radar-based Swing Caddie unit at the same time as the Skytrak, and the reported total carry distances from it were within 2-5 yards of the SkyTrak (usually shorter) for each of these shots...so I suppsoe that is a sort of 2nd confirming data point.

Thoughts ??

[Rogala]

First level and set up skytrak per the many instructions on this site and above. Gunghogolf has an an excellent article on same. I personally have my unit on a concrete floor next to my mat and used the case legs to bring the unit up to lelvel of mat. If unit is sitting where it can shake or move when u hit u will get odd results. After that hit a series of say 10 iron shots and look at average typical ranges. Looking at individual shot parameters is useless Put ball on a tee to eliminate mat influences. Then go from there. Input average parameters into an online flight algorithm and see what the results are

OK, I just took the feet off the unit and am heading to the garage now to hit some iron shots. Will report back.

I am using the device in DIRECT mode, BTW, as my network is a little spotty in the garage at the moment. I could also try USB mode tomorrow as I just ordered an extra long active cable per something I read from Gunghogolf on another thread.

Again, thanks for your patience with a SkyTrak newbie.

I will be using the radar based Swing Caddie as well as the SkyTrak, just so I have the data being collected / reported in two different ways.

[Rogala]

3on3putt

You wroite: "You should be carrying at least 245 if your club head speed is over 100."

So I have been told during various clubfitting sessions at places like Cool Clubs and Hot Links in AZ, and also others. I have an ex-caddie swing which was tailored to playing in Texas (where I lived for 17 years) and which is based on a medium, arcing trajectory with a right to left bias.

In irons, it has been called a "trap-draw" by various professionals. With my driver, it is sort of a "going draw" with a lower than normal launch angle off of a 9.5 degree driver. I have experimented with a higher lofted driver which does give me a higher launch angle without modifying my swing, and I did carry these a few yards longer (maybe 5-15 yards? with a 12 degree driver) but then I get near-ero roll....always under 5 yards under normal ground conditions...and I lost yards overall.

In Texas, when averaged over all conditions, I generally drove it around 260-270 with roll and was able to play to my 2-3 handicap very regulalry and even win or finish well in a few local events (city championship, local mid-am events, etc.) and even a few regional events. I now live in the very rainy Pacific Northwest, and with roll over all coniditions, I average under 255.

My comfortable go-no-go distance to carry hazards is 230 yards and has been so since I moved here. As a younger man, I might have felt comfortable trying to clear something 240, but only in favorable wind conditions, or to gain some significant playing advantage.

As I wrote elsewhere, I am not an "explosive power" type golfer and never really sought to play like one. I acutally play much more hickory-shafted golf these days than I do modern golf...and a great drive with a 1920s era hickory brassie (12 degrees loft) goes maybe 225-230 maximum for me with carry and roll out here in the NW....but I find it more enjoyable as the longest downwind driver I ever hit back in Texas. The virtues of hickory are many....but ego building long driving is not really one of them.

[Fhacker]

First level and set up skytrak per the many instructions on this site and above. Gunghogolf has an an excellent article on same. I personally have my unit on a concrete floor next to my mat and used the case legs to bring the unit up to lelvel of mat. If unit is sitting where it can shake or move when u hit u will get odd results. After that hit a series of say 10 iron shots and look at average typical ranges. Looking at individual shot parameters is useless Put ball on a tee to eliminate mat influences. Then go from there. Input average parameters into an online flight algorithm and see what the results are

[3on3putt]

So are others seeing more realistic spin numbers? Curious to know because it seems a fair amount of us are seeing it pretty low.

I don't pay much attention to spin except for driver. So I can't necessarily say how accurate I think the spin numbers are. But I do know that the carry distances are spot on to real life and so are the ball flights. I have 100% confidence in my unit in those regards.

I don't know if it's been mentioned here yet but make sure your grooves are clean and that you aren't launching knuckle balls because there's dirt caked in the grooves.

[3on3putt]

225-240 is a bit low for club head speeds of 100-104. One of those estimates is off. You should be carrying at least 245 if your club head speed is over 100.

[RAH5]

So are others seeing more realistic spin numbers? Curious to know because it seems a fair amount of us are seeing it pretty low.

[Bubba22]

Here is a search on some threads dealing with low spin and Skytrak.


https://www.google.com/search?q=skyt...obile&ie=UTF-8

[Ronsc1985]

Of course, and I would agree with all your thoughts....although the launch monitor I was using in that particular session actually had one input the club loft data for each club as part of its set up. In the case of the Rogues, I entered the lofts right off the Callaway spec chart and it spit out smash factor numbers based on the data.

That being said, I am (sadly) aware that equipment companies today are doubling down on the same vanishing-loft game that almost every big club manufacturer has played since the 1980s....labelling a 5 iron as their 6 iron or even a 7 iron. ;-)

In my very limited experience with juiced up clubs like the Rogue, I can say that I find them waaaay too hot for my tastes. My play set irons are set up (PW to 5-iron) at 46, 42, 38, 34, 30, 26 in terms of the loft...so 2 degrees strong versus classical numbers.

You can read this link

https://www.tutelman.com/golf/design/swing2.php

for a pretty detailed explanation of the effects of loft on ball flight parameters.

[3on3putt]

Will do tomorrow. I'll make sure all the clubs are clean and I will try positioning the ball logo right at the unit. I was hitting with a brand new Callaway ERC ball, a brand new Bridgestone ball and a brand new Vice ball earlier today when I saw the wonky (over inflated) carry and total yardage numbers....since (as soon as I saw the over-inflated distnaces) I suspected the ball...hence my trying 3 different brands.

I had the SkyTrak set up on a seperate mat right next to my hitting mat...but the top surface of both mats are exactly the same height, and the top surfaces of both are about 3/4" to 1" above a concrete floor due to the mats being mounted to a plywood base.

However (!!): I just realized that I have the SkyTrak in the metal case with feet on it.

Do I maybe need to remove the feet or just remove the other mat and put the unit with feet right on the concrete floor so that the extra feet height cancels out the plywood base height of the hitting mat ?? That way the bottom surace of the metal box would be the same exact hight as the top surface of the hitting mat.

The bottom of the Skytrak must be level with your hitting surface. So if the 2 mats are the same height, the legs on the metal case will need to be unscrewed all the way up so that the unit can go down as low as possible. Try removing the Skytrak from the metal case and have it sit on your separate mat to ensure that the unit is level with your hitting mat and see if that makes a difference.

Also make sure to zero out the tilt and roll in the skytrak app. I don't think tilt or roll will affect spin but always worth doing anyway.

[Mirek_62]

My only clue is that the RPM Backspin numbers are ludicrously low....around 2-3K RPM when I know they should be 6-7K RPM based on other simulation and Real Life results.

Thanks !!!

Backspin has a significant effect on carry distance. You can check how it affects it here

https://flightscope.com/products/trajectory-optimizer/

The type of mattress has a great influence on the backspin. It is enough that the contact of the club head is earlier (even minimal) with the mattress than with the ball and the backspin drops dramatically.

[Rogala]

Fresh, white, premium (urethane cover) ball with logo towards unit? SkyTrak is very good at measuring backspin, as long as logo faces camera.

BTW, I love your website....great articles....and solid advice...