Polarization, Recoil Weight & MgR/I demystified?

[Irvin]

It is easy to calculate what any any increase in weight will do to RW, weight, balance, and SW. I = mr^2 For RW 10 g added 31 cm from balance point increases (31*31*.010) 9.61 points. For SW 10 g added 9 cm below SW axis goes up (9*9*.010) 0.81 points. Weight goes up 10 g but to calculate balance result you need the original balance and weight.

 

[Irvin]

IMO adding more than a few grams all at once unless you’re trying to obtain the specs you’re used to playing with is a mistake. Add only a few grams at a time then play with it for a week to evaluate the mods and determine if you’re moving the specs in the right direction. Any big chances like adding 2 g at 12 o’clock increasing SW, RW, weight, and balance all at once is a mistake. Adding 2 g at the butt is a less drastic approach.

 

[K1Y]

Something I dont understand: If looking at optimal specs for a person with a height of 5,7. Should you focus on the RW or the MgR/i? I can't seem to figure out what numbers would result in a 21 MgR/i and a 158 RW?

 

[Yamin]

Something I dont understand: If looking at optimal specs for a person with a height of 5,7. Should you focus on the RW or the MgR/i? I can't seem to figure out what numbers would result in a 21 MgR/i and a 158 RW?

I'm about the same height and tried some of this stuff.. I'd say neither are worth giving too much attention to, though I do like the one racket in my possession with my recommended RW. It doesn't do anything magical compared to anything else that is stable, 18x20 blade v7 is at that RW. Vcore Pro 95 comes out at 21 mgr/i, I couldn't make contact with the ball. One racket doesn't have the balance I'd like, the other didn't have the SW which are much more important.

Maybe if you were modding two rackets to your target spec range and wanted to focus on these it could be useful...

 

[K1Y]

I'm about the same height and tried some of this stuff.. I'd say neither are worth giving too much attention to, though I do like the one racket in my possession with my recommended RW. It doesn't do anything magical compared to anything else that is stable, 18x20 blade v7 is at that RW. Vcore Pro 95 comes out at 21 mgr/i, I couldn't make contact with the ball. One racket doesn't have the balance I'd like, the other didn't have the SW which are much more important.

Maybe if you were modding two rackets to your target spec range and wanted to focus on these it could be useful...

Thanks for sharing your exp. I do notice a difference in a high and low MgR/i so that made me curious to try it for myself. I want to try modding the specs of my 2 speed mp's towards optimal MgR/i and optimal RW. I could do Mgr/i focus on one of them and RW focus on of them. But apparently its impossible to get Mgr/i to 21 if you want 158 RW. Thats the main thing I was wondering.

 

[Yamin]

Thanks for sharing your exp. I do notice a difference in a high and low MgR/i so that made me curious to try it for myself. I want to try modding the specs of my 2 speed mp's towards optimal MgR/i and optimal RW. I could do Mgr/i focus on one of them and RW focus on of them. But apparently its impossible to get Mgr/i to 21 if you want 158 RW. Thats the main thing I was wondering.

You should absolutely be able to get very close at least. Just not at what may be your desired spec. Something like 345 gram, 33 balance, 340 swing weight gets you there.

 

[Trip]

The pursuit of some magical MGR/i "holy grail" number, be it 21 or otherwise, is largely fruitless on its own. You need to figure out what applies to your body, biomechanics and play style, and that very often isn't an MGR/i of exactly 21 -- for those of us over 6-feet tall, it's often a bit lower (to account for a longer arm), and for those who are shorter, it can very well be slightly higher, but that can't be interpreted as a precise scale, either. And neither can @Brando's table of supposedly optimal recoil weight for people's height, although it's a darn good starting point which happens to align with my experience, and that of many others). In the end, there are a lot of other vectors in play, and there's still no substitute for on-court experience.

That said, if you had to pick whether pursuing MGR/i or recoil weight was more worth-while, I'd be inclined to give the slight edge to recoil weight, mostly because it's easier for the average person to comprehend. But still, as @Yamin stated above, there are plenty of examples where the numbers just don't line up for a person. At that point, whether they're an outlier or not doesn't matter to them; all they know is, the numbers don't appear to make sense for them, and at that point, they're probably better off simply picking a racquet that feels good enough, optimizing strings as best they can, and then putting all the remaining effort into lessons, training and match play.

One last comment specifically on behalf of @K1Y; while 345g/33cm/340sw would get you a nice and high 20.9 MGR/i and 157.5rw, you can't ignore the weight. It's still a 345g stick and 340 swing weight, and while not insurmountable (heck, I swung a 350sw stick at 9 years old!), it's still a decent amount away from what he's used to, especially if he wants a more flicky/maneuverable doubles setup, whereby a spec such as the one I offered in his other thread (332g/32.6cm/328sw/158rw/20.8mgr/i), would give him almost all of the same core benefits, minus some bludgeoning force, in exchange for much more maneuverability. You could also add some free power back in by creating a bouncier/more explosive string bed, which is also excellent for doubles. So it all comes down to how beefy a spec the player can handle and what they'll be doing with it -- more head-heavy, higher swing weight and firmer string bed for singles and higher-level/strength players; more head-light, lower-swing weight and softer string bed for doubles and lower-level/strength players -- in general.

 

[K1Y]

The pursuit of some magical MGR/i "holy grail" number, be it 21 or otherwise, is largely fruitless on its own. You need to figure out what applies to your body, biomechanics and play style, and that very often isn't an MGR/i of exactly 21 -- for those of us over 6-feet tall, it's often a bit lower (to account for a longer arm), and for those who are shorter, it can very well be slightly higher, but that can't be interpreted as a precise scale, either. And neither can @Brando's table of supposedly optimal recoil weight for people's height, although it's a darn good starting point which happens to align with my experience, and that of many others). In the end, there are a lot of other vectors in play, and there's still no substitute for on-court experience.

That said, if you had to pick whether pursuing MGR/i or recoil weight was more worth-while, I'd be inclined to give the slight edge to recoil weight, mostly because it's easier for the average person to comprehend. But still, as @Yamin stated above, there are plenty of examples where the numbers just don't line up for a person. At that point, whether they're an outlier or not doesn't matter to them; all they know is, the numbers don't appear to make sense for them, and at that point, they're probably better off simply picking a racquet that feels good enough, optimizing strings as best they can, and then putting all the remaining effort into lessons, training and match play.

One last comment specifically on behalf of @K1Y; while 345g/33cm/340sw would get you a nice and high 20.9 MGR/i and 157.5rw, you can't ignore the weight. It's still a 345g stick and 340 swing weight, and while not insurmountable (heck, I swung a 350sw stick at 9 years old!), it's still a decent amount away from what he's used to, especially if he wants a more flicky/maneuverable doubles setup, whereby a spec such as the one I offered in his other thread (332g/32.6cm/328sw/158rw/20.8mgr/i), would give him almost all of the same core benefits, minus some bludgeoning force, in exchange for much more maneuverability. You could also add some free power back in by creating a bouncier/more explosive string bed, which is also excellent for doubles. So it all comes down to how beefy a spec the player can handle and what they'll be doing with it -- more head-heavy, higher swing weight and firmer string bed for singles and higher-level/strength players; more head-light, lower-swing weight and softer string bed for doubles and lower-level/strength players -- in general.

Once again like in the other thread, thank you so much for sharing and writing this out for me and the rest. This post gave a lot of clarity and I would suggest someone pin it somewhere. As you know the specs you recommended are working out so far.

Now I have two less important questions on this topic but still I was wondering about it:

1. Newly crowned queen of NYC coco gauff has two large strips of lead in the throat of her rackets. If I understand this MgR/i thing correctly, weight at that spot (close, but below the balance point) raises MgR/i by a lot. Can we assume she uses a relatively high MgR/i, something near 21?

2. Can you tell by the way someone their swing looks if they are using a high or low MgR/i?

 

[Power Player]

I wouldn't obsess over MGRi or recoil weight. I made the mistake of sharing that info in another thread and a few people bashed it like I was saying it worked for sure and is the magic number to finding optimal specs - it is not.

What I would suggest is noting what specs you play best with. Measure the weight/SW and balance and put it in your iphone notes or whatever you use. You will forget them after if not.

In my case, I threw bunch of racquets I used well into the calculator and many of them hit around the same number. I then looked at the height chart and saw that the number lined up with my height. The only thing it does for me is explains why I have played well with some light frames and then as well with heavier ones.

So I think what it does is show that physique makes a huge difference in what frames I can use compared to someone else. If you are a muscular person with a football build and have shorter arms instead of a long wingspan, then it is very possible that you may have better racquet head control without struggling with a heavier frame. Whereas a taller player with a long wingspan may consider a 305 gram frame heavier than you do. Or maybe not, it's very subjective.

It's really hard to tell what works for you without playing matches under pressure and seeing which gives you the most confidence and control. I say this because it really doesn't matter what MGRI Coco uses, that is meaningless since she has some of the most elite fitness in the sport and is incredibly skilled at tennis.

The recoil weight number seems like a potential guideline once you have used a good amount of frames, have developed technique and can make a note of what has been working for you - timing wise, when playing matches.

 

[Pneumated1]

The pursuit of some magical MGR/i "holy grail" number, be it 21 or otherwise, is largely fruitless on its own. You need to figure out what applies to your body, biomechanics and play style, and that very often isn't an MGR/i of exactly 21 -- for those of us over 6-feet tall, it's often a bit lower (to account for a longer arm), and for those who are shorter, it can very well be slightly higher, but that can't be interpreted as a precise scale, either. And neither can @Brando's table of supposedly optimal recoil weight for people's height, although it's a darn good starting point which happens to align with my experience, and that of many others). In the end, there are a lot of other vectors in play, and there's still no substitute for on-court experience.

That said, if you had to pick whether pursuing MGR/i or recoil weight was more worth-while, I'd be inclined to give the slight edge to recoil weight, mostly because it's easier for the average person to comprehend. But still, as @Yamin stated above, there are plenty of examples where the numbers just don't line up for a person. At that point, whether they're an outlier or not doesn't matter to them; all they know is, the numbers don't appear to make sense for them, and at that point, they're probably better off simply picking a racquet that feels good enough, optimizing strings as best they can, and then putting all the remaining effort into lessons, training and match play.

One last comment specifically on behalf of @K1Y; while 345g/33cm/340sw would get you a nice and high 20.9 MGR/i and 157.5rw, you can't ignore the weight. It's still a 345g stick and 340 swing weight, and while not insurmountable (heck, I swung a 350sw stick at 9 years old!), it's still a decent amount away from what he's used to, especially if he wants a more flicky/maneuverable doubles setup, whereby a spec such as the one I offered in his other thread (332g/32.6cm/328sw/158rw/20.8mgr/i), would give him almost all of the same core benefits, minus some bludgeoning force, in exchange for much more maneuverability. You could also add some free power back in by creating a bouncier/more explosive string bed, which is also excellent for doubles. So it all comes down to how beefy a spec the player can handle and what they'll be doing with it -- more head-heavy, higher swing weight and firmer string bed for singles and higher-level/strength players; more head-light, lower-swing weight and softer string bed for doubles and lower-level/strength players -- in general.

I stumbled upon RW theory last week by accident checking out a frame in an unrelated thread. I've been aware of MGR/i for some time but never gave it too much thought, but there's something about RW that pulls me in, and I'm pretty sure I can validate the theory's claims. I decided a few years ago to go to much lighter static weight and swing weight (in light player frames even) because I'm getting older, like everyone, but I've struggled and feel like I'm working harder with lighter frames. I'm a shade under 6' 2" with pretty long arms, and I've concluded after some modding and experimenting that I can swing a 340-345g frame with a swing weight anywhere from 320-330 (depending upon balance) and balance of 31.1cm to 31.5 (depending upon swing weight) a lot easier than I can a depolarized light player frame. And my MGR/i typically falls between 20.5 and 20.9. If there's any truth to the RW charts and guides, I've been playing a RW likely 15-20 pts lighter than I should for my height.

And these are the specs that have always worked for me. Even when I was totally ignorant of RW and MGR/i, I would mod my frames by feel close to their theories' recommended specs. So I agree with you and Power Player that you have to work all this out through experience on court and consider your own body type and preferences. And a good example of this is the fact that I'm more swing weight sensitive than anything, so 328-330sw is my limit, which significantly limits my retail options for a RW of 171-172. But considering I own a pair of v4 UP 18x20s, they're easy (almost perfect) for achieving my specs. My Artengo TR 960 Control Tours are a little harder because they feel way over listed swing weight. I can get them there but with a few compromises (like no hoop mods, which they need).

And I don't own a Briffidi and don't know of anyone in my area who owns a SW machine, so I'm also doing some guessing and may be shocked when I finally tweak things perfectly (by feel) and find out what I actually have.

 

[Tranqville]

I'm a shade under 6' 2" with pretty long arms, and I've concluded after some modding and experimenting that I can swing a 340-345g frame with a swing weight anywhere from 320-330 (depending upon balance) and balance of 31.1cm to 31.5 (depending upon swing weight) a lot easier than I can a depolarized light player frame. And my MGR/i typically falls between 20.5 and 20.9. If there's any truth to the RW charts and guides, I've been playing a RW likely 15-20 pts lighter than I should for my height.

I'm also 6'2'' with long arms, and those are almost exactly my preferred specs. I prefer slightly higher SW, in 330-335 range. I believe 6'2'' @Trip also likes 330 SW, and the rest of his specs are very similar. Maybe we can start a 170 RW club or someting And yes, @Brando RW hypothesis is awesome and works in practice for many players!

 

[Pneumated1]

I'm also 6'2'' with long arms, and those are almost exactly my preferred specs. I prefer slightly higher SW, in 330-335 range. I believe 6'2'' @Trip also likes 330 SW, and the rest of his specs are very similar. Maybe we can start a 170 RW club or someting And yes, @Brando RW hypothesis is awesome and works in practice for many players!

Actually, I'm finding that I can tolerate more swing weight than I thought with polarized frames. I'll be hitting this evening with a pair of UP 18x20s modded to ~340g, 31.1cm, and 320-325sw (swing weight is a guess unfortunately). And I'll also try my Artengo TR960 Control Tours modded to 340g, 32cm, and ~330-335sw (again, a guess). The Artengos, with their slightly thicker beams, just felt chunkier at the same weight as the UPs, so I figured I'd experiment with higher swing weight and slightly more even balance with them to find my limits. But there's a chance I'll strip the 3-4g I have in the head and add more under the butt cap to get my RW number. I'm learning that it's heavy and high swing weight or very head light balance to do so. And yeah, where do I sign up for the 170-172 RW club? I doubt it'll have too many members.

 

[Tranqville]

And yeah, where do I sign up for the 170-172 RW club? I doubt it'll have too many members.

Most ATP pros are in 170s, as far as I know.

 

[dr. godmode]

where do I sign up for the 170-172 RW club? I doubt it'll have too many members.

I was in this club with my ETs and 2018 VC95's, but since switching to the Whiteout I can't get my RW that high without a 340+ SW or 355+ static which is just too much for me after a set and a half. I would have probably preferred my Whiteouts with a stock balance of 31cm instead of 32cm to achieve that RW, but whatever I'm happy with them not even though it took a very long time to get my specs right

 

[Pneumated1]

I was in this club with my ETs and 2018 VC95's, but since switching to the Whiteout I can't get my RW that high without a 340+ SW or 355+ static which is just too much for me after a set and a half. I would have probably preferred my Whiteouts with a stock balance of 31cm instead of 32cm to achieve that RW, but whatever I'm happy with them not even though it took a very long time to get my specs right

I'm learning that some frames just won't get there. My Tengos are good examples. They swing/feel great for me with 10g under the butt cap and a gram or two at 12. That gets them to approx. 335g, 325-328sw, 32cm, and 162 RW. All else equal, I'd have to push swing weight to 335+ to achieve the 'club' RW. Seems you have to meet some frames on their terms or let them go. Thin and light platforms like my UPs and Evo work right into specs, and they respond great. I didn't care for the Artengos tonight at my recommended RW. They either need to be stock swing weight and very head light or carry a lot of tip weight. I'll keep trying, but the UPs are money.

Btw, the specs in your signature look great to me, regardless of RW.

 

[dr. godmode]

I'm learning that some frames just won't get there. My Tengos are good examples. They swing/feel great for me with 10g under the butt cap and a gram or two at 12. That gets them to approx. 335g, 325-328sw, 32cm, and 162 RW. All else equal, I'd have to push swing weight to 335+ to achieve the 'club' RW. Seems you have to meet some frames on their terms or let them go. Thin and light platforms like my UPs and Evo work right into specs, and they respond great. I didn't care for the Artengos tonight at my recommended RW. They either need to be stock swing weight and very head light or carry a lot of tip weight. I'll keep trying, but the UPs are money.

Btw, the specs in your signature look great to me, regardless of RW.

They are quite nice, MGRI is just over 21 as well which really works for my forehand.

 

[vokazu]

Recoil weight, the polarization index, and MgR/I are different measures of racquet polarization calculated from the same variables of weight, balance & swingweight (SW):

THE FORMULAS:
Recoil Weight = SW - (wt. in kg. x (cm balance - 10)²)
The Polarization Index = Recoil Weight ÷ Weight in grams
MgR/I = (wt. in kg x 980.5 x cm balance) ÷ (SW + (20 x kg wt. x cm balance) - (100 x kg wt.))

THE IDEAS
Recoil Weight is like swingweight except its axis is the balance point instead of 10cm (your hand). The higher the RW, the more polarized the frame: >170 is very polarized; <150 is very depolarized.
The Polarization Index looks at RW in proportion to mass to arrive at a simpler polarization measure: most racquets hover around 0.50 PI, with > 0.50 PI being more polarized and <0.5 PI being less polarized.
MgR/I is used to adjust how quickly the hoop comes through your swing so as to fit arm length and swing style by varying weighting and its positioning to achieve your ideal racquet head lag. (The higher the MgR/I, the less polarized the frame and the faster the hoop comes through.) <20 is very polarized; >21.5 is very depolarized.

It’s easy to assume that these measures move consistently visa vie one another, as if a lower recoil weight means a less polarized frame, and so, a higher MgR/I every time. While this is mostly true, it’s not the hard n’ fast rule people think. As you’ll see from the case of Andrey Rublev’s racquet customization, there are differences among the three polarization measures that are easy to miss and quite confusing, too, unless you dive a bit deeper:

Rublev’s Racquet vs. its stock specs*	In Year	Length [cm]	Weight [grams]	Balance [cm]	Swing Weight	Recoil Weight	Polariz’n [RW/Wt]	MgR/I
Stock Gravity Pro	2018	68.6	332	32.0	332	171.3	0.52	20.37
Rublev’s Gravity Pro	2019	68.6	359	31.0	335	176.7	0.49	20.92

* All specs are strung specs, as they will be throughout this post.

Rublev’s racquet tech adds 20.4 grams around 16cm up the handle, probably in the form of gobs of silicon, plus 1.6g of tape at 10 & 2. Then Rublev adds an overgrip and, after all is stuck n’ done, balance has dropped from 7 HL to 10 HL. Meanwhile, swingweight has risen (barely), and it makes sense because mass added anywhere on a frame increases SW (even if sometimes unnoticeably).

What’s surprising is the rise in RW. I’d think that adding even that much weight that far up a 22cm handle would reduce recoil. But only the polarization index decreases, from 0.52 to 0.49, which doesn’t seem to make sense. How does a mod job lower the polarization index but raise recoil weight when they’re supposed to be the same thing?

Breaking it down, a 5g overgrip increases polarization from 0.5156 to 0.5159 and increases RW from 171.3 to 173.7. OK, that makes sense. What’s less obvious is that the other added weight (a whopping 22 grams of it) rose proportionally more than its distribution raised recoil weight. Indeed, weight increased 8% while RW increased only 3%, making the polarization index fall, by the numbers. This means that if the weight is big enough and/or its distribution is far enough from the poles, then a frame’s polarization index (being a ratio of RW) can drop even as its recoil weight (an absolute value) rises.

Here’s another fun fact. MgR/I rises when weight is added below the balance point but falls from weighting above it. This makes MgR/I different from recoil weight and the polarization index in that it can indicate which end is more polarized.

How exactly does MgR/I change with weight distribution? When weight is added under the buttcap, MgR/I barely rises. From there, the higher up weighting is placed, the more MgR/I increases until mass is placed at the balance point, where MgR/I begins to drop back down. The higher mass is placed above the balance point, the more MgR/I drops, ending up lower than the starting MgR/I. This table displays the phenomenon when 9 grams of weighting is moved up a frame with stock specs of 320g, 33cm balance, 325 SW, and 20.54 MgR/I:

9g AT VARYING LOCATIONS	butt	handle	b/p	hoop	tip
9-gram Location:​	1 cm	17 cm	33 cm	50 cm	68 cm
Resulting MgR/I:​	20.55	20.73	20.71	20.50	20.07
MgR/I change from 20.54:​	+0.01	+0.19	+0.17	-0.04	-0.47

While I find these patterns fascinating, you might well ask, “Do I really need to know this MgR/I stuff?” The short answer is no, not unless you’re, say, micro-adjusting down the 21.5 MgR/I of your 350g frame for added spin.

‘Truth is, the most popular racquets are between 20.4 and 20.8 MgR/I. Not coincidentally, that’s the standard deviation of 2022’s top-sellers, which average 20.58 MgR/I. In this midrange there are so many combinations of weight, balance, and SW that can reach any one MgR/I that seeking MgR/I as some kind of a benchmark is almost meaningless.

Take Wilson’s Ultra 100 v.4 with its light, very evenly distributed weighting and 4 HL balance. Compare that to Yonex’s Vcore 95 with its heavy-ish, more handle-weighted 7 HL balance. For all their differences, these frames have virtually identical MgR/Is and swingweights:

	of Year	Length [cm]	Weight [grams]	Balance [cm]	Swing Weight	Recoil Weight	Polariz’n [RW/Wt]	MgR/I
Wilson Ultra 100 v.4​	2022	68.6	318	33.0	317	148.8	0.47	20.78
Yonex Vcore 95​	2020​	68.6​	326​	32.0​	316​	158.2​	0.49​	20.79​

‘Think, maybe, such pairings are outliers? Try this one on for size:

	of Year	Length [cm]	Weight [grams]	Balance [cm]	Swing Weight	Recoil Weight	Polariz’n [RW/Wt]	MgR/I
Head Boom MP	2022​	68.6​	315​	32.7​	318​	155.7​	0.49​	20.51
Tecnifibre Tfight RS 305	2020​	68.6​	323​	33.5​	333​	154.9​	0.48​	20.51

So I say, don’t bother with MgR/I if you haven’t already. Get to know your favorite recoil weight instead. It’ll tell you a lot about why some racquets with the same specs can feel “mysteriously” different.

But if you’ve already started down the MgR/I rabbit hole, consider that spec measures are most useful in combination versus targeting some absolute value in any one of them, as some tend to do with MgR/I. Together, specs paint a vivid picture of how a racquet can perform. Learning how to see that in the numbers is fun (to us geeks at least), and getting to enjoy the results on court, the most fun of all.

Thanks so much for this. Can you please help me check if my calculation here is correct?

I'm now using your formula for my racquet, Toalson Power Swing 400 with Fairway leather grip and one overgrip:

Weight: 431 gram
Balance: 32.2 cm
Swing weight: 392

THE FORMULAS:
Recoil Weight = SW - (wt. in kg. x (cm balance - 10)²)
The Polarization Index = Recoil Weight ÷ Weight in grams
MgR/I = (wt. in kg x 980.5 x cm balance) ÷ (SW + (20 x kg wt. x cm balance) - (100 x kg wt.))


Recoil weight:
392 - (0.431x (32.2-10)²) =
392 - (0.431 x (22.2)²) =
392 - (0.431 x 492.84) =
392 - (212.41404) =
179.58596
(polarized?)


Polarisation index:
179.58596 : 431 = 0.416672761
(depolarized)


MgR/I = (0.431 x 980.5 x 32.2) : ((392 + (20 x 0.431 x 32.2) - (100 x 0.431) )=

13,607.5751 : ((392 + 277.564) - (43.1)) =

13607.5751 : ((669.564) - 43.1)) =
13607.5751 : 626.464 =
21.7212403267
(depolarized)

Conclusion: my racquet is depolarized.

Is that all correct?

Thanks in advance!

 

[tim-ay]

I'm also 6'2'' with long arms, and those are almost exactly my preferred specs. I prefer slightly higher SW, in 330-335 range. I believe 6'2'' @Trip also likes 330 SW, and the rest of his specs are very similar. Maybe we can start a 170 RW club or someting And yes, @Brando RW hypothesis is awesome and works in practice for many players!

there is no coincidence here. everybody likes those specs. lol

 

[Irvin]

@vokazu yes

 

[vokazu]

@vokazu yes

Thanks so much!

 

[dl32]

I’m 6’2” and play with a unique 95 sq head pro stock that is flexible but very stable with descent power - 22mm box beam.

I’ve tinkered haphazardly until I stumbled onto to these threades. I have all the tools needed to customize except measuring twist weight and stiffness.

Below was my final spec considering I have a solid 1HBH, big forehand, solid slice and descent net game:

Static 346.8
Bal 312
Sw 331

Results:

RW 175.13
MrG/I 20.69
PI .505

It took time to figure this out, but this spec is super for my game. Playing style and body style will impact this stuff.

This setup feels like the frame rips through the air and crushes the ball. Zero issue with spin generation from a tight 16/19.

Fun stuff!

 

[EggSalad]

Recoil Weight and to a lessor extent MrG/I has been an awesome discovery for me. I greatly appreciate the time that has gone in to making this thread. Like @Power Player , I had an idea of what static, SW and balance I liked to play with and how those racuqets benefited me. What recoil & MrG/I have done is given me a road map to make very minor tweaks to what I thought was my preferred set up, and those tweaks have really helped. In general, it has been adding a little more static weight and SW than I thought I prefered, with the added weight primarily being polarized. More of the weight has been in the butt cap than at 12 o'clock, but that is due to the initial balance of my racquet (elevate v3).

Getting the MrG/I +21 seems like a tall task, but I have gotten it to around 20.7 (I think) and the racquet just swings to naturally for me on all shots. The recoil weight alignment to height is really the best starting point as well, and is spot on for me.

 

[Trip]

@EggSalad - Great data point. For as much as this stuff seems like unicorn dust to so many, it does bare some merit, and is worth trying. That said, on the flip side, it's not the end-all, be-all answer to any player without fundamentals in place -- ie. most sub 3.x-level rec hackers are not going to fix their game by making sure their MGR/i or RW values are aligned with their body type and play/swing style. You need to have at least some pedigree under your belt for this stuff to really shine, but if you do, it can (will?) usually make a difference.

 

[K1Y]

I am 5'7" and 21.3 MGR/I on the Artengo 990 power pro has been working really well.

 

[Brando]

Thanks so much for this. Can you please help me check if my calculation here is correct?

I'm now using your formula for my racquet, Toalson Power Swing 400 with Fairway leather grip and one overgrip:

Weight: 431 gram
Balance: 32.2 cm
Swing weight: 392

THE FORMULAS:
Recoil Weight = SW - (wt. in kg. x (cm balance - 10)²)
The Polarization Index = Recoil Weight ÷ Weight in grams
MgR/I = (wt. in kg x 980.5 x cm balance) ÷ (SW + (20 x kg wt. x cm balance) - (100 x kg wt.))


Recoil weight:
392 - (0.431x (32.2-10)²) =
392 - (0.431 x (22.2)²) =
392 - (0.431 x 492.84) =
392 - (212.41404) =
179.58596
(polarized?)


Polarisation index:
179.58596 : 431 = 0.416672761
(depolarized)


MgR/I = (0.431 x 980.5 x 32.2) : ((392 + (20 x 0.431 x 32.2) - (100 x 0.431) )=

13,607.5751 : ((392 + 277.564) - (43.1)) =

13607.5751 : ((669.564) - 43.1)) =
13607.5751 : 626.464 =
21.7212403267
(depolarized)

Conclusion: my racquet is depolarized.

Is that all correct?

Thanks in advance!

Hi @vokazu. While your calculations are correct (as others have confirmed), your conclusion is not. Your beast of a frame is polarized, not depolarized. In fact, it's among the most polarized frames I've ever read of, outside of maybe one of @Shroud's frames. Check out the OP of this thread if you want to learn more about what makes a frame polarized. But it essentially means that most of the weight is at one end or the other or both ends (like Richard Gasquet's). In your case, with a 21.7 MgR/I, most of the weight is in the handle. Am curious. What have you weighted it with?

 

[tele]

Hi @vokazu. While your calculations are correct (as others have confirmed), your conclusion is not. Your beast of a frame is polarized, not depolarized. In fact, it's among the most polarized frames I've ever read of, outside of maybe one of @Shroud's frames. Check out the OP of this thread if you want to learn more about what makes a frame polarized. But it essentially means that most of the weight is at one end or the other or both ends (like Richard Gasquet's). In your case, with a 21.7 MgR/I, most of the weight is in the handle. Am curious. What have you weighted it with?

are you sure a lot of the weight is not in the throat?

 

[vokazu]

Hi @vokazu. While your calculations are correct (as others have confirmed), your conclusion is not. Your beast of a frame is polarized, not depolarized. In fact, it's among the most polarized frames I've ever read of, outside of maybe one of @Shroud's frames. Check out the OP of this thread if you want to learn more about what makes a frame polarized. But it essentially means that most of the weight is at one end or the other or both ends (like Richard Gasquet's). In your case, with a 21.7 MgR/I, most of the weight is in the handle. Am curious. What have you weighted it with?

I only replaced the original grip (synthetic) with Fairway leather grip, I didn't add anything inside the handle. I also use one overgrip.

The racquet has built in weight at 3 and 9 o'clock of the hoop (like Pro Staff PWS). I suspect it also has built in weight at the top of the hoop.

 

[tele]

as far as i know this racquet would be considered "depolarized". I just checked using the customization tool, and to get to that spec from, say, a prostaff 97, you would need to add most of the weight near the throat.

 

[vokazu]

are you sure a lot of the weight is not in the throat?

I'm curious to know where the manufacturer put the weight on Toalson Power Swing racquets. I know it has weights at 3 and 9 o'clock of the hoop, because its bulging at those locations.

 

[socallefty]

I like the same racquet specs between the time I weighed 170 pounds and 220 pounds. Is that “normal”?

 

[Brando]

are you sure a lot of the weight is not in the throat?

Polarization can be so confusing that even the guy who started this thread toward solving the confusion around polarization can still get it wrong!

Yes, @tele, you’re right: this is a depolarized frame. What confused me was the high recoil weight, which often indicates a polarized frame. But, by its very definition in my OP, the lower the Polarization Index drops below 0.50 PI, the more depolarized it is. And at 0.42, that is one depolarized frame.

My mistake is a neat case study in how all three measures of polarization (the PI, RW, and MgR/I) are far more informative when used together than alone. If you just told me that a frame’s RW is 180, I’d guess it’s polarized, with a lotta weight consolidated at tip &/or tail. If you then added that its MgR/I is 21.7, I’d refine my assessment and say most of its weight is in the handle. If you finally added that its polarization index is 0.42, I’d say cripes! @tele is right! A lotta that weight is distributed up into the throat too, making it both evenly and heavily weighted below the balance point. And, above the balance point, it’s much lighter but still evenly weighted in its lightness.

 

[vokazu]

Here are the calculations for my 4 racquets:

Racquet 1:
Weight: 441 grams
Balance: 32.4 cm
Swing weight: 407
Recoil Weight: 185.72384
Polarization Index: 0.4211424943
MgR/I: 21.5977606418


Racquet 2:
Weight: 448 grams
Balance: 31.9 cm
Swing Weight: 400
Recoil Weight: 185.13472
Polarization Index: 0.4132471428571429
MgR/I: 21.85958965654952

Racquet 3:
Weight: 436 grams
Balance: 32.5 cm
Swing Weight: 401
Recoil Weight: 180.275
Polarization Index: 0.4134747706422018
MgR/I: 21.68178058676654

Racquet 4:
Weight: 440 grams
Balance: 32.4 cm
Swing Weight: 414
Recoil Weight: 193.2256
Polarization Index: 0.4391490909090909
MgR/I: 21.3365612407

My favourite racquet is racquet 3, followed by 1, then 2, then 4.

 

[Brando]

Those are true beasts, @vokazu! The only thing I'd be able to wield them for is cracking walnuts!

 

[vokazu]

Here are the calculations for my 4 racquets:

Racquet 1:
Weight: 441 grams
Balance: 32.4 cm
Swing weight: 407
Recoil Weight: 185.72384
Polarization Index: 0.4211424943
MgR/I: 21.5977606418


Racquet 2:
Weight: 448 grams
Balance: 31.9 cm
Swing Weight: 400
Recoil Weight: 185.13472
Polarization Index: 0.4132471428571429
MgR/I: 21.85958965654952

Racquet 3:
Weight: 436 grams
Balance: 32.5 cm
Swing Weight: 401
Recoil Weight: 180.275
Polarization Index: 0.4134747706422018
MgR/I: 21.68178058676654

Racquet 4:
Weight: 440 grams
Balance: 32.4 cm
Swing Weight: 414
Recoil Weight: 193.2256
Polarization Index: 0.4391490909090909
MgR/I: 21.3365612407

My favourite racquet is racquet 3, followed by 1, then 2, then 4.

Racquet 2 is the best for serving, Very high 1st serve percentage with it! I wonder why?

 

[extremespeed]

334,50 gr / 32.1 cm / 319 SW - Extreme Tour for advanced 13 years old - one of the best in Poland and Spain in his group age. Strong 164 cm and 54 kg, played before with Extreme MP.

MGR/l - 21,04
RW - 155,61
Polarization index - 0,46

What do you think about this racquet for this boy? It’s good mgr, rw for him?

 

[dr. godmode]

334,50 gr / 32.1 cm / 319 SW - Extreme Tour for advanced 13 years old - one of the best in Poland and Spain in his group age. Strong 164 cm and 54 kg, played before with Extreme MP.

MGR/l - 21,04
RW - 155,61
Polarization index - 0,46

What do you think about this racquet for this boy? It’s good mgr, rw for him?

Seems fine. Regardless of skill, probably better to go for a 100. Why not take the extra forgiveness when you can?

IMO, tuning for specs is beyond the scope of his needs. I wouldn't bother delving into spec optimization until he mostly stops growing, physically and technically.

Best practice for junior development is probably to minimize gear tinkering. Whether conscious or not, any gear switching will cause the player to make adjustments to their game which, more often than not, limited progress, as these adjustments are typically lateral changes (not regressive or progressive) and just not worth worrying about.

 

[GAS]

334,50 gr / 32.1 cm / 319 SW - Extreme Tour for advanced 13 years old - one of the best in Poland and Spain in his group age. Strong 164 cm and 54 kg, played before with Extreme MP.

MGR/l - 21,04
RW - 155,61
Polarization index - 0,46

What do you think about this racquet for this boy? It’s good mgr, rw for him?

It's old man specs. Modern game requires a polarized racquet because that helps with wrist lag. That's PI>50%

 

[extremespeed]

Seems fine. Regardless of skill, probably better to go for a 100. Why not take the extra forgiveness when you can?

IMO, tuning for specs is beyond the scope of his needs. I wouldn't bother delving into spec optimization until he mostly stops growing, physically and technically.

Best practice for junior development is probably to minimize gear tinkering. Whether conscious or not, any gear switching will cause the player to make adjustments to their game which, more often than not, limited progress, as these adjustments are typically lateral changes (not regressive or progressive) and just not worth worrying about.

100 was a rocket launcher for him, not that much control and he was a bit lazy with 100… with 98 he is obligated to have better footwork…

Just trying to get him the best specs for Extreme Tour. Main goal is health, but also versatile development. He is playing all the year on clay court outdoor.

 

[extremespeed]

It's old man specs. Modern game requires a polarized racquet because that helps with wrist lag. That's PI>50%

Why old man specs? So how to get specs around 21 mgr/l and over 50% Pl… or when you go over 50% Pl you cannot have 21 mgr/l? Sorry, but I am learning about this. Pretty new topic for me…

 

[GAS]

Why old man specs? So how to get specs around 21 mgr/l and over 50% Pl… or when you go over 50% Pl you cannot have 21 mgr/l? Sorry, but I am learning about this. Pretty new topic for me…

You already had more than a few people telling you these specs are wrong for your kid on the other thread.

I'm watching Sinner play now and it's insane that your 13yo kid is playing with a much heavier racquet. Sinner's PI also above 50%.

Anyway, if you want to know more about these things, you can start here:

Recoilweight, Polarization -

Polarization and recoilweight determine the weight distribution of the racket.

impactingtennis.com

 

[Conrado85]

São especificações do velho. O jogo moderno requer uma raquete polarizada porque isso ajuda no atraso do pulso. Isso é PI>50%

Old specs? João Fonseca's MGR/I is over 21 and RW is within his height range. What works for one player may not work for another.

 

[GAS]

E você que idade tem?

 

[aaron_h27]

You already had more than a few people telling you these specs are wrong for your kid on the other thread.

I'm watching Sinner play now and it's insane that your 13yo kid is playing with a much heavier racquet. Sinner's PI also above 50%.

Anyway, if you want to know more about these things, you can start here:

Recoilweight, Polarization -

Polarization and recoilweight determine the weight distribution of the racket.

impactingtennis.com

Sinner's racket is head heavy and higher SW so not exactly accurate to say "he's playing with a heavier racket than sinner"

 

[ZeroandOne]

Sinner's racket is head heavy and higher SW so not exactly accurate to say "he's playing with a heavier racket than sinner"

Totally agree.
For those whose who didn't quite understand:

@aaron_h27 meant low static but high sw and hh balance sticks can feel heavy, sluggish and challenging. They definitely do. Especially when serving, volleying and playing defence.

Slightly heavier hl sticks with reasonable sw might feel easier to swing for most people, imo. Within reasonable specs.

@extremespeed I have to say @dr. godmode gave an important consideration, and that's the headsize. Make tennis as easy as possible. I can't imagine him not finding a 100 he can't control. That's nonsense. Sweetspots are so much bigger. Perhaps he craved a bit of weight to help slow down a fast swing, or he didn't groove with the stringjob.

In terms of possible customization, tell us more. Does he have problems with any shots? Fh, bh, on the run shots, lowballs, highballs? Changing direction? Cc, down the line? Can he maneuver the stick well at the net? Does he need more pop? Does he hit too flat? Too spinny? Can he return fast serves well? Does the racquet twist excessively? Is the ball dropping short outside the sweetspot? Does he feels like he is pulling the stick through the air? Does he feel lag when swinging? Or is it a pushing sensation, or something in between? Is the swing comfortable, or does he feels like he's micro adjusting, or muscling too many shots?

It's a terrible idea to customize only because you're chasing a number.

Often times my on-court experiences guides my decisions how I customize my sticks.

 

[extremespeed]

Sinner's racket is head heavy and higher SW so not exactly accurate to say "he's playing with a heavier racket than sinner"

325 / 33.3 cm / 340 sw - I heard that this are Sinner specs, but not sure…

 

[extremespeed]

Totally agree.
For those whose who didn't quite understand:

@aaron_h27 meant low static but high sw and hh balance sticks can feel heavy, sluggish and challenging. They definitely do. Especially when serving, volleying and playing defence.

Slightly heavier hl sticks with reasonable sw might feel easier to swing for most people, imo. Within reasonable specs.

@extremespeed I have to say @dr. godmode gave an important consideration, and that's the headsize. Make tennis as easy as possible. I can't imagine him not finding a 100 he can't control. That's nonsense. Sweetspots are so much bigger. Perhaps he craved a bit of weight to help slow down a fast swing, or he didn't groove with the stringjob.

In terms of possible customization, tell us more. Does he have problems with any shots? Fh, bh, on the run shots, lowballs, highballs? Changing direction? Cc, down the line? Can he maneuver the stick well at the net? Does he need more pop? Does he hit too flat? Too spinny? Can he return fast serves well? Does the racquet twist excessively? Is the ball dropping short outside the sweetspot? Does he feels like he is pulling the stick through the air? Does he feel lag when swinging? Or is it a pushing sensation, or something in between? Is the swing comfortable, or does he feels like he's micro adjusting, or muscling too many shots?

It's a terrible idea to customize only because you're chasing a number.

Often times my on-court experiences guides my decisions how I customize my sticks.

Extreme Tour is a good racquet for 13 years old tennis player?

Hi, My son is 13 years old and he is playing tennis already 8 years. He is one of the best in Poland and Spain in his category. When he was 11 he started to play with 300 gr racquet Babolat Pure Aero, then he sign a contract with Head and when he was 12 he switched to Head Extreme MP. Later...

tt.tennis-warehouse.com

 

[dr. godmode]

I want to reiterate, I think it’s been lost:

You cannot optimize specs for a rapidly growing player.

You’d have to be changing things monthly to keep up with technical development, physical development and literally the human changing size and shape.

Constant racquet changes are not good for player development.

Keep it simple, use stock, matched racquets and maybe add some lead at 12 or 10/2 in small increments as ball speeds increase.

 

[Conrado85]

I want to reiterate, I think it’s been lost:

You cannot optimize specs for a rapidly growing player.

You’d have to be changing things monthly to keep up with technical development, physical development and literally the human changing size and shape.

Constant racquet changes are not good for player development.

Keep it simple, use stock, matched racquets and maybe add some lead at 12 or 10/2 in small increments as ball speeds increase.

Small increments every 2-3 months as he grows wouldn't be bad. 1 mm of balance at times, 1-2 points of SW, 1-2 grams of weight at a time. These are modifications that, for a developing teenager, are quickly adapted to their biomechanics.

 

[extremespeed]

I want to reiterate, I think it’s been lost:

You cannot optimize specs for a rapidly growing player.

You’d have to be changing things monthly to keep up with technical development, physical development and literally the human changing size and shape.

Constant racquet changes are not good for player development.

Keep it simple, use stock, matched racquets and maybe add some lead at 12 or 10/2 in small increments as ball speeds increase.

Thank you. Common sense. We will stick for now with Extreme Tour (stock with leather) and later with Auxetic 2.0 I suppose and adding a bit weight when he will get stronger. I am going to match him raquets for now.

 

[FuzzyYellowBalls]

I want to reiterate, I think it’s been lost:

You cannot optimize specs for a rapidly growing player.

You’d have to be changing things monthly to keep up with technical development, physical development and literally the human changing size and shape.

Constant racquet changes are not good for player development.

Keep it simple, use stock, matched racquets and maybe add some lead at 12 or 10/2 in small increments as ball speeds increase.

This could be a scary truth for the forum, but most will probably gloss over it.