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

[Rogala]

I’ve seen this too. Almost the same thing so we must have similar swings. I don’t have the readings in front of me but on a really flush shot I’m carrying up to 185 with a 7-iron.

Using a new ball, logo toward the unit, unit same height as the mat.

Backspin reading is consistently sub-4000.

Fiberbuilt mat, which I’ve read can really depress the spin.

It doesn’t really bother me that much because the shot shape is way more important to me but I have certainly questioned it.

I am guessing I’d carry it farther on unit than on the course. I’m able to really dial in a swing with no consequences. But 185 has to be too far.

Hmmm...now I am starting to get tremendously concerned about the SkyTrak.

Spin numbers are important to me as spin defines trajectory. Of course I knew a SkyTrak can never be as accurate as a combo-based system, but I was hoping it would be more accuraten than the radar-based Swing Caddie. The Swing Caddie is off about 200-300 RPM, but it is CONSISTENTLY off...meaning you can rely on simply adding 200-300 RPM on every swing, and the numbers being correct. (Note: I tested the Swing Caddie against both a Trackman and a high end camera-based system).

I am also worried about how course simulation software is going to deal with this output being so odd unless one can fiddle with the settings in a club-specific way within the sim software.

For reference: IRL, my best, best 7-iron carry with no wind and normal conidtions, is approximately 165 yards (155-160 is more typical). IRL, my best 8-iron carry is approximately 145 yards (135-140 is more typical).

Note: BTW, I am a former 2-3 handicap golfer (was actually scratch forone season) who nowadays plays comfortably off a 6 or 7...now that I have eight-year old twins, and not so much time for golf. Point being, I will claim to having more-repeatable-than-average swing, though not a truly first-class or explosively powerful one...just a little trap draw which I learned in the caddy yard 30 years ago.

I found some swing data from another camera based system I tried out in February of 2020, and my 7-iron backspin was a bit lower than I recalled...right around 6,300 RPM on average with an 80-82 mph clubhead speed. My 8-iron jumps up to nearly 8,000 RPM with a 76-78 mph clubhead speed.

5-iron clubhead speed is right around 88 with 4,500 RPM (best shots carry right around 185 yards) and 6-iron at 85 mph and 5,300 RPM (best shots carry 175 yards)...so all that spin and clubhead data hangs together, logically. I play a Bridgestone Speed Ball or a Titleist NXT....which are a little hotter than some other balls. Driver carries 225-240 or so on a clubhead spped of 100-104. Note: I was never an explosive hitter. My top driver club head speed (44" club) when I was in my 30s was 107-108.

I will be comparing all this data to SkyTrak over the weekend and will try to post it for reference.

[RAH5]

I’ve seen this too. Almost the same thing so we must have similar swings. I don’t have the readings in front of me but on a really flush shot I’m carrying up to 185 with a 7-iron.

Using a new ball, logo toward the unit, unit same height as the mat.

Backspin reading is consistently sub-4000.

Fiberbuilt mat, which I’ve read can really depress the spin.

It doesn’t really bother me that much because the shot shape is way more important to me but I have certainly questioned it.

I am guessing I’d carry it farther on unit than on the course. I’m able to really dial in a swing with no consequences. But 185 has to be too far.

[Rogala]

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

Hitting off a mat takes some spin off (about 15-20% compared to turf), but you should be getting at least 5.5K spin with that ball speed, with a premium ball.

Make sure you're looking at total spin and spin axis (setting in SkyTrak session settings), so any sidespin component doesn't subtract from the backspin number.

Also make sure you select 7-iron when testing. If SkyTrak cannot measure spin for some reason (no logo in view to key in on), it may guess at the spin based on the club you've selected.

Side note: 76-80 mph club speed with 7-iron will not produce 116-120 mph ball speed. 7-iron smash factor is about 1.35 at most (tour level strike), which is 108 mph ball speed from 80 mph clubhead speed.

OK, I didn't have the logo pointing at unit. Will try that. I also chaged the session setting to spin axix, but it only jumped up the total RPM numbers by about 200RPM.

I then reset the unit and tried again (still no logo pointing at unit), This time I got 76 mph and 109 mph for club and ball speed with a 7-iron and an RPM reading of about 4,500. My 8-iron came up as 74 mph and 101 mph club and ball with 5,600 RPMs. So maybe something is still off there.

I tested it with a Swing Caddy unit on the same swings, and those numbers were (IMO) spot on with my real life performance.

Somehow, the Swing Caddy (a $450 unit) is reporting carry and total distance more accurately than SkyTrak is at the moment (at least the way I was using SkyTrak). The Siwng Caddy is radar based and sits 6 feet BEHIND the ball, while the SkyTrak is sitting slghtly in front and alongside the ball.

[GungHoGolf]

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

Hitting off a mat takes some spin off (about 15-20% compared to turf), but you should be getting at least 5.5K spin with that ball speed, with a premium ball.

Make sure you're looking at total spin and spin axis (setting in SkyTrak session settings), so any sidespin component doesn't subtract from the backspin number.

Also make sure you select 7-iron when testing. If SkyTrak cannot measure spin for some reason (no logo in view to key in on), it may guess at the spin based on the club you've selected.

Side note: 76-80 mph club speed with 7-iron will not produce 116-120 mph ball speed. 7-iron smash factor is about 1.35 at most (tour level strike), which is 108 mph ball speed from 80 mph clubhead speed.

[Rogala]

I am a new user, using Skytrak on a PC in direct mode.

SkyTrak is reporting my clubhead speed and ball speed for an easy 7-iron at about 76-80 MPH and 116-120 MPH respectively...which seem sort of accurate based on my swing and results IRL.

It is reporting the carry distance, however, at around 176 yards and the overall distance close to 200 yards. It should be 155-165 yards with no wind based on IRL results.

What could be going on ??

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.

Has anyone else seen this sort of combined RPM lowballing and yardage inflation ?? How to get SkyTrak to read properly / correct this inflation ??

Thanks !!!