Who Cares about Recoil Weight?

[susari]

Corresponding to table posted in the page 1

With the minimum value of RW of player height reached

Given: SW=RW+MR^2

Anyone have tried below?

RW=MR^2
RW>MR^2
RW<MR^2

Just wondering how is the feel/shock?

 

[Tranqville]

Customizer Note: increasing the SW to weight ratio increases RW, as does lowering balance via tail weighting because both increase polarization.

When the player is accostomed to a certian racquet static weight and SW, and wants to change the RW, which value should we aim to "protect" more - the static weight or SW? Should we aim to also "protect" the balance, if possible?

So, in practical sense, just as an example, let's say I'd like to customize Radical MP - with strung specs of 318g static weight, 4 HL balance, 323 SW - which translates into 155 RW. I'd like to achieve 172RW: let's say, with 335 SW, 335g static weight, and 7 HL balance. Looks perfect, but I wonder if this is indeed the best possible setup?

 

[Irvin]

When the player is accostomed to a certian racquet static weight and SW, and wants to change the RW, which value should we aim to "protect" more - the static weight or SW? Should we aim to also "protect" the balance, if possible?

So, in practical sense, just as an example, let's say I'd like to customize Radical MP - with strung specs of 318g static weight, 4 HL balance, 323 SW - which translates into 155 RW. I'd like to achieve 172RW: let's say, with 335 SW, 335g static weight, and 7 HL balance. Looks perfect, but I wonder if this is indeed the best possible setup?

I’m not Brando but let me try to answer your question. You don’t feel weight you feel torgue. Torque is the balance point time the weight. You can add mass to the butt of the racket and you won’t change torque or SW much but your RW goes up my mr^2. Your balance at 4HL is 33 cm from the butt so the mass you need to add to increase RW 17 points is mass = 17/(33*33.) So adding 17 g at the butt should raise the RW 17 points, SW and torque increases very little and you new balance (31.3 cm) will be lower. I expect the racket will feel about the same. Of course it will be hard getting 17 g at the butt.

 

[Shroud]

I’m not Brando but let me try to answer your question. You don’t feel weight you feel torgue. Torque is the balance point time the weight. You can add mass to the butt of the racket and you won’t change torque or SW much but your RW goes up my mr^2. Your balance at 4HL is 33 cm from the butt so the mass you need to add to increase RW 17 points is mass = 17/(33*33.) So adding 17 g at the butt should raise the RW 17 points, SW and torque increases very little and you new balance (31.3 cm) will be lower. I expect the racket will feel about the same. Of course it will be hard getting 17 g at the butt.

your sig cracked me up. If you ad 2 overgrips you can probably get close to 17g. IIRC my gamma grip 2 was 8g each.

 

[Irvin]

your sig cracked me up. If you ad 2 overgrips you can probably get close to 17g. IIRC my gamma grip 2 was 8g each.

There’s more issues to adding 2 OGs other than building the grip up 2 sizes. The center of balance for the 2 OGs is the mid point or about 9 cm from butt 24 cm below the balance point which adds less RW and increases the torque. Then you still need more mass to get the RW up. The 2 OGs should raise the RW ~10 points

 

[Brando]

When the player is accostomed to a certian racquet static weight and SW, and wants to change the RW, which value should we aim to "protect" more - the static weight or SW? Should we aim to also "protect" the balance, if possible?

So, in practical sense, just as an example, let's say I'd like to customize Radical MP - with strung specs of 318g static weight, 4 HL balance, 323 SW - which translates into 155 RW. I'd like to achieve 172RW: let's say, with 335 SW, 335g static weight, and 7 HL balance. Looks perfect, but I wonder if this is indeed the best possible setup?

I like @Irvin and @Shroud's innovative solutions. My more general answer is that I personally "protect" swingweight. I always have a target SW in mind when customizing. Depending on the frame, that SW will change, a lower SW for a heavier frame and higher one for lighter frames. So what SW range would you ideally want in that particular frame, @Tranqville?

When I've answered that question, I start thinking about MgR/I and adjust weight and balance accordingly. My least protected spec is balance. That said, I have a personal lower limit of 31.5cm. Below that, I tend to lose tip awareness. Of course, all this is how I personally approach customizing for recoil weight. But there's no "right" answer. It all depends on what changes you're personally most sensitive to, and least.

 

[Tranqville]

So what SW range would you ideally want in that particular frame, @Tranqville?

My preferred range overall is 330-340, and I feel that for Head MP, with its naturally flatter output, 340 would work best. For a bit spinnier frame like T-Fight, 330 looks just about right.

 

[Brando]

I happen to have played the 360 Radical MP for 3 years and consider it a polarizer's dream. I had mine modded to 170wr and 334sw via 3 grams of plasticine under the buttcap and 3 grams of tungsten tape at noon. Assuming your 2023 version is on-spec, 10g and 5g would get you: 338g, 32.3cm, 340sw, 16tw, 172rw, 20.42 MgR/I. Of course you'll have your own way of customizing this frame, @Tranqville. I'm only agreeing with you that this is a quite doable mod. Sweet!

 

[Brando]

Corresponding to table posted in the page 1
With the minimum value of RW of player height reached

Given: SW=RW+MR^2
Anyone have tried below?

RW=MR^2
RW>MR^2
RW<MR^2

Just wondering how is the feel/shock?

You got me thinking on this one, @susari. As the Moment of Inertia, MR^2 measures how hard it is to rotate an object. It depends not only on mass but also on how far that mass is from the rotational axis (in this case the balance point) of an object (a racquet). The farther that distance for a given mass (or points of mass), the larger MR^2.

Your formula also means that RW=SW-MR^2, such that the lower the moment of inertia for a given RW, the higher SW will be, making the frame feel harder to swing while producing more power and less impact shock. Likewise, the higher the moment of inertia for a given RW, the lower SW will be, making the frame easier to swing while producing less power and more impact shock (assuming all other things equal).

As for RW=MR^2, it mathematically means that swingweight would have to be double the value of both moment of inertia and recoil weight, such that X=2X–X. This would again make the frame harder to swing but with less impact shock.

Anyway, that’s my stab at answering this. But I’m no physicist, and maybe someone else can address this question better than I. Any thoughts, @Irvin?

 

[susari]

You got me thinking on this one, @susari. As the Moment of Inertia, MR^2 measures how hard it is to rotate an object. It depends not only on mass but also on how far that mass is from the rotational axis (in this case the balance point) of an object (a racquet). The farther that distance for a given mass (or points of mass), the larger MR^2.

Your formula also means that RW=SW-MR^2, such that the lower the moment of inertia for a given RW, the higher SW will be, making the frame feel harder to swing while producing more power and less impact shock. Likewise, the higher the moment of inertia for a given RW, the lower SW will be, making the frame easier to swing while producing less power and more impact shock (assuming all other things equal).

As for RW=MR^2, it mathematically means that swingweight would have to be double the value of both moment of inertia and recoil weight, such that X=2X–X. This would again make the frame harder to swing but with less impact shock.

Anyway, that’s my stab at answering this. But I’m no physicist, and maybe someone else can address this question better than I. Any thoughts, @Irvin?

Thanks...

I'm thingking of
Let say SW = 340

1. RW=170 and MR^2=170 (RW value = MR^2)
2. RW=175 and MR^2=165 (RW > MR^2)
3. RW=165 and MR^2=175 (RW < MR^2)

 

[TysonMcMuffin]

@Brando Im trying to understand this article from TWU. When they say “… a high twistweight, large-headed racquet may also have a low swingweight. So even though it is stable right-to-left, it is unstable tip-to-butt. When it comes to power, movement in one direction can cancel stability in another, or contrariwise, stability in one direction can more than make up for instability in another”

Does this mean that racquets with high recoilweight can have lower twistweight and racquets with lower recoilweight can should have higher twistweight?

I’m curious because when I add even the slightest amount of lead at 12 to my ezone they feel extremely unstable and hard to play with. If I don’t hit the ball in the center it feels like the launch angle is crazy high. I don’t mind lead at 3&9. But I got a pro stock racquet the other day and its twistweight was extremely low (13.00 on briffidi) but it had high recoilweight and I didn’t feel the instability at all. I found out that the racquet was near my optimal recoilweight as well according to your chart (6’2). Static Weight 335 grams, SW 333, Balance 32. ~171 RW. It still had a similar effect to the ezone where when I hit off center shots they would launch higher than normal but the effect was exaggerated with the ezone and would happen much more frequently. I’m also pretty sure technique is not as big a factor because i’m currently at a 10.9 utr so usually when I get a stock racquet I can play with whatever it is and I have little complaints.

 

[aaron_h27]

@Brando Im trying to understand this article from TWU. When they say “… a high twistweight, large-headed racquet may also have a low swingweight. So even though it is stable right-to-left, it is unstable tip-to-butt. When it comes to power, movement in one direction can cancel stability in another, or contrariwise, stability in one direction can more than make up for instability in another”

Does this mean that racquets with high recoilweight can have lower twistweight and racquets with lower recoilweight can should have higher twistweight?

I’m curious because when I add even the slightest amount of lead at 12 to my ezone they feel extremely unstable and hard to play with. If I don’t hit the ball in the center it feels like the launch angle is crazy high. I don’t mind lead at 3&9. But I got a pro stock racquet the other day and its twistweight was extremely low (13.00 on briffidi) but it had high recoilweight and I didn’t feel the instability at all. I found out that the racquet was near my optimal recoilweight as well according to your chart (6’2). Static Weight 335 grams, SW 333, Balance 32. ~171 RW. It still had a similar effect to the ezone where when I hit off center shots they would launch higher than normal but the effect was exaggerated with the ezone and would happen much more frequently. I’m also pretty sure technique is not as big a factor because i’m currently at a 10.9 utr so usually when I get a stock racquet I can play with whatever it is and I have little complaints.

What's the twistweight on the Ezone ?

 

[TysonMcMuffin]

Twistweight varies slightly with swingweight but usually 13.15 - 13.25. It usually varies with swingweight but most ezone’s come extremely underspec. I have 5 and only 1 is above 313 strung swingweight. That’s with 16g tourbite in the frame.

 

[TheSlicer]

just f*king play

 

[TysonMcMuffin]

just f*king play

Will do . Thank you!

 

[Brando]

@Brando Im trying to understand this article from TWU. When they say “… a high twistweight, large-headed racquet may also have a low swingweight. So even though it is stable right-to-left, it is unstable tip-to-butt. When it comes to power, movement in one direction can cancel stability in another, or contrariwise, stability in one direction can more than make up for instability in another”

Does this mean that racquets with high recoilweight can have lower twistweight and racquets with lower recoilweight can should have higher twistweight?

I’m curious because when I add even the slightest amount of lead at 12 to my ezone they feel extremely unstable and hard to play with. If I don’t hit the ball in the center it feels like the launch angle is crazy high. I don’t mind lead at 3&9. But I got a pro stock racquet the other day and its twistweight was extremely low (13.00 on briffidi) but it had high recoilweight and I didn’t feel the instability at all. I found out that the racquet was near my optimal recoilweight as well according to your chart (6’2). Static Weight 335 grams, SW 333, Balance 32. ~171 RW. It still had a similar effect to the ezone where when I hit off center shots they would launch higher than normal but the effect was exaggerated with the ezone and would happen much more frequently. I’m also pretty sure technique is not as big a factor because i’m currently at a 10.9 utr so usually when I get a stock racquet I can play with whatever it is and I have little complaints.

First off, @TysonMcMuffin, your handle makes me chuckle just typing it. So thanks for brightening my day. As to your first question, yes, racquets with high recoil weight can have lower twistweights and racquets with lower recoil weight can have higher twistweights.

That said, the two measures are often correspondingly high (or low) because a higher SW often results from weight being distributed liberally around the hoop. But some frames are built differently, such that there are much thinner layers of graphite around 9&3 than around 12. And it sounds like your Ezones are in that camp at 13.15-13.25tw.

From your description, I’m guessing your new pro stock frame’s 171rw feels pretty much “on” to you other than its low TW issue. If I have that right, I may have a viable answer.

You mentioned that your Ezones are 313sw and below. Even if their RWs were similar to your pro stock, that’d be a very different, much higher MgR/I, route to 171rw than your pro stock’s 335g, 32cm, 333sw, 20.41 MgR/I takes you to get there. Put simply, the very head-lightness of your Ezones is exaggerating the effects of their low twistweights, making them feel all the more unstable on off-center hits. And when you tip weight them, not only does it fail to address your TW issue, it may throw off your RW & SW enough to make them swing sluggish.

If I’m right, it highlights an important point: No spec lives in a vacuum. They all exist in the context of one another. And if one spec (whether it be TW, RW, or beam width, etc.) is way out of your preferred margins, it can significantly throw off the feel of the frame, even if you’re a 10.9 UTR player.

 

[TysonMcMuffin]

@Brando Thank you for the kind words and thank you for taking the time to respond!

First off I just noticed that your prestige tour has extremely close specs to my pro stock tgt 348.1 that feels amazing so I'm sure your racquet feels great as well. Would be curious to see the twistweight on it.

I read on impacting tennis website that recoilweight is a measure of a racquet's overall stability. I haven't tried to match my ezone's to a recoilweight of 171 because of what you said. I would either have to put a lot of weight in the handle and would end up with an extremely heavy racuqet with extremely headlight balance and low swingweight.

Why is it the case that the headlightness of a racquet exaggerates the effect of low twistweight?

For example, theoretically, if a racquet was 345 grams, Balance 30.5, SW 317, Recoilweight would be around 172 and MGRI would be around 21. Theoretically, it seems like this would be a good racquet. Would it just be incredibly hard to time the ball since SW is so low and MGRI is high? Or is there another factor at play that I'm missing that tells us why a spec like this isn't more common (at least at the not pro level because I know they need higher SW).

 

[aaron_h27]

First off, @TysonMcMuffin, your handle makes me chuckle just typing it. So thanks for brightening my day. As to your first question, yes, racquets with high recoil weight can have lower twistweights and racquets with lower recoil weight can have higher twistweights.

That said, the two measures are often correspondingly high (or low) because a higher SW often results from weight being distributed liberally around the hoop. But some frames are built differently, such that there are much thinner layers of graphite around 9&3 than around 12. And it sounds like your Ezones are in that camp at 13.15-13.25tw.

From your description, I’m guessing your new pro stock frame’s 171rw feels pretty much “on” to you other than its low TW issue. If I have that right, I may have a viable answer.

You mentioned that your Ezones are 313sw and below. Even if their RWs were similar to your pro stock, that’d be a very different, much higher MgR/I, route to 171rw than your pro stock’s 335g, 32cm, 333sw, 20.41 MgR/I takes you to get there. Put simply, the very head-lightness of your Ezones is exaggerating the effects of their low twistweights, making them feel all the more unstable on off-center hits. And when you tip weight them, not only does it fail to address your TW issue, it may throw off your RW & SW enough to make them swing sluggish.

If I’m right, it highlights an important point: No spec lives in a vacuum. They all exist in the context of one another. And if one spec (whether it be TW, RW, or beam width, etc.) is way out of your preferred margins, it can significantly throw off the feel of the frame, even if you’re a 10.9 UTR player.

This is a really good point, if one spec is out of range it can negatively affect the on court performance. Having a optimal MGR/I & RW but the balance is too head heavy, or the twistweight is too high/low it won't play well IMO.

Then you have powerful rackets that play well with 320 SW, and then some low-powered rackets that need 330-335.

So every racket is like basically starting over. I realized regardless of the frame I'm using I prefer 6pts+ HL, ~160 RW and a twistweight around 13.5 then I adjust from there

I just started learning about beam width too....I don't really like thicker beams because they generally come with too high of a twistweight and that's a spec you can't change.

 

[TysonMcMuffin]

This is a really good point, if one spec is out of range it can negatively affect the on court performance. Having a optimal MGR/I & RW but the balance is too head heavy, or the twistweight is too high/low it won't play well IMO.

Then you have powerful rackets that play well with 320 SW, and then some low-powered rackets that need 330-335.

So every racket is like basically starting over. I realized regardless of the frame I'm using I prefer 6pts+ HL, ~160 RW and a twistweight around 13.5 then I adjust from there

I just started learning about beam width too....I don't really like thicker beams because they generally come with too high of a twistweight and that's a spec you can't change.

I’ve found this out the hard way through experimentation. Of course there’s a range of “correct” or “good enough” variables but it’s hard to know how to identify what’s wrong with whatever setup I make and how to isolate and fix the problem. I’m so close to just saying f it and switch to using a blade pro or PA 98 that I love in stock form but I already have like 5 ezones lol.

 

[aaron_h27]

I’ve found this out the hard way through experimentation. Of course there’s a range of “correct” or “good enough” variables but it’s hard to know how to identify what’s wrong with whatever setup I make and how to isolate and fix the problem. I’m so close to just saying f it and switch to using a blade pro or PA 98 that I love in stock form but I already have like 5 ezones lol.

I don't really believe in playing a racket with no modifications or "stock" as y'all say...My 2022 Ezone 98's came in at 303 SW strung which is basically unplayable without modifications. Tennis Warehouse is always giving us optimistic SW numbers but I always find that my numbers are way lower. Also if you buy 3 of same frame you have to match them to the same specs and that also requires modification.

But yeah it's nice when a racket is pretty much close to the spec you want and you only need an overgrip and maybe a few grams at 3 & 9.

 

[Brando]

@Brando Thank you for the kind words and thank you for taking the time to respond!

First off I just noticed that your prestige tour has extremely close specs to my pro stock tgt 348.1 that feels amazing so I'm sure your racquet feels great as well. Would be curious to see the twistweight on it.

I read on impacting tennis website that recoilweight is a measure of a racquet's overall stability. I haven't tried to match my ezone's to a recoilweight of 171 because of what you said. I would either have to put a lot of weight in the handle and would end up with an extremely heavy racuqet with extremely headlight balance and low swingweight.

Why is it the case that the headlightness of a racquet exaggerates the effect of low twistweight?

For example, theoretically, if a racquet was 345 grams, Balance 30.5, SW 317, Recoilweight would be around 172 and MGRI would be around 21. Theoretically, it seems like this would be a good racquet. Would it just be incredibly hard to time the ball since SW is so low and MGRI is high? Or is there another factor at play that I'm missing that tells us why a spec like this isn't more common (at least at the not pro level because I know they need higher SW).

You’re welcome, @TysonMcMuffin. What a subtle question. A common irony in our game is how top players know diddly about their sticks, while hackers like me dive down a rabbit hole to know what plays best for them (overcompensate much?). That a UTR 10.9 is asking such questions is both refreshing and unusual. So let’s dive into it:

Your thinking is spot-on and logical. The missing variable is how twistweight is measured. Your Briffidi TW attachment (wonderful machine!) twists the racquet around on its head to measure the hoop’s resistance to movement around its Y-axis. The more mass placed farther from the axis, the higher the TW measurement. You know this, but I review it to set this up: Mass placed ON the balance point, at 12, barely gets registered, if at all, because this mass doesn’t resist movement along the Y-axis.

In the case of your Ezones, this barely matters because there ain’t much mass at noon anyway. But in the case of your pro stock Extreme Tour (360+?), there’s a lot more weight on the balance point. One might say that this means the Briffidi under-measures TW on high SW frames like your TGT348.1, but IMO, that’s not so. When we strike a ball off-center, the mass at noon makes little or no difference in terms of torque produced on the racquet along Y.

But what a twistweight machine can’t measure is the real-time effect of high SW on the whole system, which we feel on both the Y and X-axes. On an off-center hit, a low-SW racquet may torque equally to a high-SW one, if all else is equal. But all else isn’t. The extra SW along the X-axis is adding racquet head speed and lowering impact vibration. This can make the frame feel noticeably more solid and stable at impact, even as it might not be (depending on how much mass we’re talking about). Make sense?

Re. our similar specs, yeah, I noticed that too and almost commented on it. ‘Glad you did because it informs our topic. (And, yes! I’m 6’1” and this is the best version of ~170rw I’ve ever swung.) I recently came to it having played a matched trio of 360 Radical MPs modded up to 171rw via 325g, 32.4cm, 333sw, 13.7-13.9tw. Similarly, my matched pair of HPT 2021s are 13.9 and 14.1tw. One might think that, being only 331sw and a 22mm box-beamed 95 t’ boot, HPT would be at least as jarring as the Radical on off-center shots. But not so, not even close. And the difference is CAP grommets.

New polymers have enabled Head to make them far lighter and stronger, but they still have the old school effect of significantly muting impact vibrations. In fact this is my favorite feature of this model. The Radicals are famously crispy frames, but this hits like the proverbial buttah, as if I’m swinging 15.5tw, except at net where it maneuvers once again like its true 14. Best of both worlds, and I couldn’t be more blown away because I’ve long dreamed of playing a full CAP frame, but one never wandered into my spec range before.

Point is, there’s more to twistweight than meets first glance, and again, each spec exists within the context of them all, even the blankety-blank grommets!

 

[aaron_h27]

@Brando Im trying to understand this article from TWU. When they say “… a high twistweight, large-headed racquet may also have a low swingweight. So even though it is stable right-to-left, it is unstable tip-to-butt. When it comes to power, movement in one direction can cancel stability in another, or contrariwise, stability in one direction can more than make up for instability in another”

Does this mean that racquets with high recoilweight can have lower twistweight and racquets with lower recoilweight can should have higher twistweight?

I’m curious because when I add even the slightest amount of lead at 12 to my ezone they feel extremely unstable and hard to play with. If I don’t hit the ball in the center it feels like the launch angle is crazy high. I don’t mind lead at 3&9. But I got a pro stock racquet the other day and its twistweight was extremely low (13.00 on briffidi) but it had high recoilweight and I didn’t feel the instability at all. I found out that the racquet was near my optimal recoilweight as well according to your chart (6’2). Static Weight 335 grams, SW 333, Balance 32. ~171 RW. It still had a similar effect to the ezone where when I hit off center shots they would launch higher than normal but the effect was exaggerated with the ezone and would happen much more frequently. I’m also pretty sure technique is not as big a factor because i’m currently at a 10.9 utr so usually when I get a stock racquet I can play with whatever it is and I have little complaints.

Twistweight has nothing to do with recoil weight but more so the players style of play and how much manuverability/spin they like to have....higher twistweight offers better stability but at the cost of maneuverability and spin. WTA players use high twistweight as they hit more linearly and with less spin than ATP players do. Low twistweight is like a 3D style of tennis where as high twistweight is more 2D.

Federer with his 90 sq inch frame would be an example of a low twistweight setup with his slice backhand, sharp angeled spinny FH's and net play compared to Serena Williams with her 104 blade as an example of high twistweight set-up, notice how she hits return winners with ease and is less likely to use angles or spin rather than just brute force. The trade off is her net play and finesse shots are non-existent or just pretty poor overall.

I think it's better to start with a lower twistweight and gradually increase as needed so you know what spec range you like.

I know doubles players like really low twistweights like in the 12's, but I find those too unstable on groundstrokes.

 

[aaron_h27]

You’re welcome, @TysonMcMuffin. What a subtle question. A common irony in our game is how top players know diddly about their sticks, while hackers like me dive down a rabbit hole to know what plays best for them (overcompensate much?). That a UTR 10.9 is asking such questions is both refreshing and unusual. So let’s dive into it:

Your thinking is spot-on and logical. The missing variable is how twistweight is measured. Your Briffidi TW attachment (wonderful machine!) twists the racquet around on its head to measure the hoop’s resistance to movement around its Y-axis. The more mass placed farther from the axis, the higher the TW measurement. You know this, but I review it to set this up: Mass placed ON the balance point, at 12, barely gets registered, if at all, because this mass doesn’t resist movement along the Y-axis.

In the case of your Ezones, this barely matters because there ain’t much mass at noon anyway. But in the case of your pro stock Extreme Tour (360+?), there’s a lot more weight on the balance point. One might say that this means the Briffidi under-measures TW on high SW frames like your TGT348.1, but IMO, that’s not so. When we strike a ball off-center, the mass at noon makes little or no difference in terms of torque produced on the racquet along Y.

But what a twistweight machine can’t measure is the real-time effect of high SW on the whole system, which we feel on both the Y and X-axes. On an off-center hit, a low-SW racquet may torque equally to a high-SW one, if all else is equal. But all else isn’t. The extra SW along the X-axis is adding racquet head speed and lowering impact vibration. This can make the frame feel noticeably more solid and stable at impact, even as it might not be (depending on how much mass we’re talking about). Make sense?

Re. our similar specs, yeah, I noticed that too and almost commented on it. ‘Glad you did because it informs our topic. (And, yes! I’m 6’1” and this is the best version of ~170rw I’ve ever swung.) I recently came to it having played a matched trio of 360 Radical MPs modded up to 171rw via 325g, 32.4cm, 333rw, 13.7-13.9tw. Similarly, my matched pair of HPT 2021s are 13.9 and 14.1tw. One might think that, being only 331sw and a 22mm box-beamed 95 t’ boot, HPT would be at least as jarring as the Radical on off-center shots. But not so, not even close. And the difference is CAP grommets.

New polymers have enabled Head to make them far lighter and stronger, but they still have the old school effect of significantly muting impact vibrations. In fact this is my favorite feature of this model. The Radicals are famously crispy frames, but this hits like the proverbial buttah, as if I’m swinging 15.5tw, except at net where it maneuvers once again like its true 14. Best of both worlds, and I couldn’t be more blown away because I’ve long dreamed of playing a full CAP frame, but one never wandered into my spec range before.

Point is, there’s more to twistweight than meets first glance, and again, each spec exists within the context of them all, even the blankety-blank grommets!

Yes I found it interesting that the TW measurement doesn't change at all with lead at 12, I figured it would move a little. Maybe if the strips were long enough it would? But with 4 inch strips of 1/4 lead tape the TW doesn't change at all.

Lead at 12 doesn't really stabilize a racket IMO unless the SW is just ridiculously low like under 310 or something. Many people assume a racket with a high SW is stable but I don't think SW is a good indicator of stability. High SW does give power and spin if you can find the sweetspot consistently.

I've also heard many times that stiff frames have a larger sweetspot but I haven't found this to be true either. Maybe because stiff frames are generally associated with thicker beams and higher twistweights? But if two rackets are spec'd the same and only difference is stiffness I don't find that the sweetspot is bigger on the stiffer frame.

 

[TysonMcMuffin]

But what a twistweight machine can’t measure is the real-time effect of high SW on the whole system, which we feel on both the Y and X-axes. On an off-center hit, a low-SW racquet may torque equally to a high-SW one, if all else is equal. But all else isn’t. The extra SW along the X-axis is adding racquet head speed and lowering impact vibration. This can make the frame feel noticeably more solid and stable at impact, even as it might not be (depending on how much mass we’re talking about). Make sense?

This is probably the sensation that I'm feeling with the Extreme Tour's (you are correct, 360+). Maybe also the silicone inside the handle dampens vibrations that makes it feel stable.

I wanted to buy the prostock in hopes of getting retail extreme tours and matching them, but the retail 360+ ET's come with much higher Twistweights (around 13 UNSTRUNG). Before I realized how high their twistweight's were, I tried putting lead at 12 and I had an unwieldy setup (I don't remember specs exactly but I know static weight was around 345, SW was around 335 and balance was around 32). I think what makes the pro stock manageable is that it's twistweight is MUCH lower. When I played with the retail ET with lead at 12 It felt EXTREMELY bulky lol.

It's funny because I think there's a common misconception that a lot of college players don't care about their specs. While I think it's still true that most of them don't, there are a lot of players that do. I play on a club team for a school that is currently top 10 in NCAA D1 ranking and one of the lower players on the lineup came out and hit with us (He was playing 6 on the lineup but he's a 13 UTR). He actually introduced me to the concept of MGRI and referred me to Impacting Tennis' Website.

He used (and is still using) an Ezone 98L heavily customized and I followed suit and bought one, but at that time I already had regular 98's so that's why I'm on this thread trying to figure out the best way to customize them.

@Brando Seeing that your racquets with similar specs to mine have a little higher Twistweight, I might try a setup with similar specs and just redistribute the weight to increase twist weight slightly. Also, as a side note, do you think weight at 3&9 increases spin or decreases spin? This is kind of a question for @aaron_h27 too because this TWU article suggests that spin increases if lead is added at 3&9 (higher TW) unless you are making contact in the bottom half of the racquet (which may well be where most pros hit, I'm not sure). Do you guys feel it increases the launch angle or decreases? I'm just curious (last question I swear).

Thank you for all the help so far by the way @Brando and @aaron_h27

 

[aaron_h27]

This is probably the sensation that I'm feeling with the Extreme Tour's (you are correct, 360+). Maybe also the silicone inside the handle dampens vibrations that makes it feel stable.

I wanted to buy the prostock in hopes of getting retail extreme tours and matching them, but the retail 360+ ET's come with much higher Twistweights (around 13 UNSTRUNG). Before I realized how high their twistweight's were, I tried putting lead at 12 and I had an unwieldy setup (I don't remember specs exactly but I know static weight was around 345, SW was around 335 and balance was around 32). I think what makes the pro stock manageable is that it's twistweight is MUCH lower. When I played with the retail ET with lead at 12 It felt EXTREMELY bulky lol.

It's funny because I think there's a common misconception that a lot of college players don't care about their specs. While I think it's still true that most of them don't, there are a lot of players that do. I play on a club team for a school that is currently top 10 in NCAA D1 ranking and one of the lower players on the lineup came out and hit with us (He was playing 6 on the lineup but he's a 13 UTR). He actually introduced me to the concept of MGRI and referred me to Impacting Tennis' Website.

He used (and is still using) an Ezone 98L heavily customized and I followed suit and bought one, but at that time I already had regular 98's so that's why I'm on this thread trying to figure out the best way to customize them.

@Brando Seeing that your racquets with similar specs to mine have a little higher Twistweight, I might try a setup with similar specs and just redistribute the weight to increase twist weight slightly. Also, as a side note, do you think weight at 3&9 increases spin or decreases spin? This is kind of a question for @aaron_h27 too because this TWU article suggests that spin increases if lead is added at 3&9 (higher TW) unless you are making contact in the bottom half of the racquet (which may well be where most pros hit, I'm not sure). Do you guys feel it increases the launch angle or decreases? I'm just curious (last question I swear).

Thank you for all the help so far by the way @Brando and @aaron_h27

I work in media and I visit a lot of college matches/pro events frequently. Customization at the college level is very common nowadays, even high level juniors are customizing their frames or at least their coaches are doing it for them. I think maybe 10-15 years ago there wasn't so much information and tools like the SW1 so people probably just used whatever off their favorite player used.

Regarding weight at 3&9 increasing or decreasing spin it depends.

Compared to a light stock frame, weight at 3&9 would increase spin because it increases the SW.

However (like swingweight & static weight) there's an optimal twistweight range for each player and how they stroke the ball. If you go over the range of your ideal TW, you are essentially carrying dead weight that can and should be used somewhere else. I experienced this recently with the Tecnifibre Tempo 298 Iga's, the twistweight was 13.7 unstrung (14.4 strung) and I'm used to playing with 13.3-13.4 strung. The manuverability is awful and the power is too much at times...every 3rd shot I am sending balls out the back of the court. I want to try using a thinner string and see if this remedies the problem of too high TW but the racket may be unsalvageble for my game and I might end up selling them. I also have another Tecnifibre Tempo 298 Iga with a 13.3 TW unstrung so that one will string up around 13.8-13.9 with a 1.15 poly. In theory that one should play much better than the first one I have because I don't need a 14.4 TW for the type of balls that I play against.

The opposite is also true, if you go too low with TW, there's no stability even though the racket may have higher "spin potential" that doesn't really matter if you're hitting every other shot off center and coughing up weak balls against a powerful opponent ;p

My racket of choice is currently the Ezone 98, im currently testing out some frames right now to see if I like anything better. I have mine spec'd out to 343g, 324 SW, 8 pts HL, 13.3 TW. I arrived at this spec by pure feel on court before I got a SW1 machine and TW adapter. This is the same spec that Kyrgios and Osaka use. It's got a nice recoil weight, manageable SW & TW and its head light enough to feel comfortable at net. There was a recent thread where someone posted the UVA team specs for the men and they were all around ~340g, 7 pts HL. (SW wasn't measured) so I think its a great starting point if you play mostly on hard courts and are using a tweener frame.

No worries about the questions, we are all passionate about improving our games and helping others. I don't consider myself one of the experts like Brando, I just have a lot of anecdotal experience, haha.

 

[TysonMcMuffin]

I work in media and I visit a lot of college matches/pro events frequently. Customization at the college level is very common nowadays, even high level juniors are customizing their frames or at least their coaches are doing it for them. I think maybe 10-15 years ago there wasn't so much information and tools like the SW1 so people probably just used whatever off their favorite player used.

Regarding weight at 3&9 increasing or decreasing spin it depends.

Compared to a light stock frame, weight at 3&9 would increase spin because it increases the SW.

However (like swingweight & static weight) there's an optimal twistweight range for each player and how they stroke the ball. If you go over the range of your ideal TW, you are essentially carrying dead weight that can and should be used somewhere else. I experienced this recently with the Tecnifibre Tempo 298 Iga's, the twistweight was 13.7 unstrung (14.4 strung) and I'm used to playing with 13.3-13.4 strung. The manuverability is awful and the power is too much at times...every 3rd shot I am sending balls out the back of the court. I want to try using a thinner string and see if this remedies the problem of too high TW but the racket may be unsalvageble for my game and I might end up selling them. I also have another Tecnifibre Tempo 298 Iga with a 13.3 TW unstrung so that one will string up around 13.8-13.9 with a 1.15 poly. In theory that one should play much better than the first one I have because I don't need a 14.4 TW for the type of balls that I play against.

The opposite is also true, if you go too low with TW, there's no stability even though the racket may have higher "spin potential" that doesn't really matter if you're hitting every other shot off center and coughing up weak balls against a powerful opponent ;p

My racket of choice is currently the Ezone 98, im currently testing out some frames right now to see if I like anything better. I have mine spec'd out to 343g, 324 SW, 8 pts HL, 13.3 TW. I arrived at this spec by pure feel on court before I got a SW1 machine and TW adapter. This is the same spec that Kyrgios and Osaka use. It's got a nice recoil weight, manageable SW & TW and its head light enough to feel comfortable at net. There was a recent thread where someone posted the UVA team specs for the men and they were all around ~340g, 7 pts HL. (SW wasn't measured) so I think its a great starting point if you play mostly on hard courts and are using a tweener frame.

No worries about the questions, we are all passionate about improving our games and helping others. I don't consider myself one of the experts like Brando, I just have a lot of anecdotal experience, haha.

Did you arrive at those ezone specs by placing lead at 12? Just wondering because I tried a very similar setup on my ezone since I used to love the vcore pro 97hd (I wish I could find more). I switched to the ezone because I could t find more. Although I matched the specs, the racquets felt completely different (of course cause of stiffness, beam width, etc).

 

[aaron_h27]

Did you arrive at those ezone specs by placing lead at 12? Just wondering because I tried a very similar setup on my ezone since I used to love the vcore pro 97hd (I wish I could find more). I switched to the ezone because I could t find more. Although I matched the specs, the racquets felt completely different (of course cause of stiffness, beam width, etc).

My Ezone 98's came in at 303 SW strung stock, so yes they needed quite a bit of lead to get to 324 SW. I have 6 grams @ 12 and 2 grams @ 3 & 9.

 

[aaron_h27]

Did you arrive at those ezone specs by placing lead at 12? Just wondering because I tried a very similar setup on my ezone since I used to love the vcore pro 97hd (I wish I could find more). I switched to the ezone because I could t find more. Although I matched the specs, the racquets felt completely different (of course cause of stiffness, beam width, etc).

Lead at 12 just raises SW without increasing TW and makes it a bit more polarized. There's nothing about lead at 12 that should hinder a frame unless you just don't like the higher SW.

 

[Irvin]

You got me thinking on this one, @susari. As the Moment of Inertia, MR^2 measures how hard it is to rotate an object. It depends not only on mass but also on how far that mass is from the rotational axis (in this case the balance point) of an object (a racquet). The farther that distance for a given mass (or points of mass), the larger MR^2.

Your formula also means that RW=SW-MR^2, such that the lower the moment of inertia for a given RW, the higher SW will be, making the frame feel harder to swing while producing more power and less impact shock. Likewise, the higher the moment of inertia for a given RW, the lower SW will be, making the frame easier to swing while producing less power and more impact shock (assuming all other things equal).

As for RW=MR^2, it mathematically means that swingweight would have to be double the value of both moment of inertia and recoil weight, such that X=2X–X. This would again make the frame harder to swing but with less impact shock.

Anyway, that’s my stab at answering this. But I’m no physicist, and maybe someone else can address this question better than I. Any thoughts, @Irvin?

Wow, you lost me on this one. The moment of inertia is the Recoil weight.

Corresponding to table posted in the page 1

With the minimum value of RW of player height reached

Given: SW=RW+MR^2

Anyone have tried below?

RW=MR^2
RW>MR^2
RW<MR^2

Just wondering how is the feel/shock?

RW=MR2 this is saying RW equals 1/2 SW
RW>MR2 this is saying RW is greater than 1/2 SW
RW<MR2 this is saying RW is less than 1/2 SW

Not really sure where this is going either. If the SW remains constant RW is inversely proportional to MR2.

 

[Brando]

Thanks, @Irvin! I just learned a valuable lesson: when it comes to physics formulas, I'm in over my head!

 

[Brando]

This is probably the sensation that I'm feeling with the Extreme Tour's (you are correct, 360+). Maybe also the silicone inside the handle dampens vibrations that makes it feel stable.

I wanted to buy the prostock in hopes of getting retail extreme tours and matching them, but the retail 360+ ET's come with much higher Twistweights (around 13 UNSTRUNG). Before I realized how high their twistweight's were, I tried putting lead at 12 and I had an unwieldy setup (I don't remember specs exactly but I know static weight was around 345, SW was around 335 and balance was around 32). I think what makes the pro stock manageable is that it's twistweight is MUCH lower. When I played with the retail ET with lead at 12 It felt EXTREMELY bulky lol.

It's funny because I think there's a common misconception that a lot of college players don't care about their specs. While I think it's still true that most of them don't, there are a lot of players that do. I play on a club team for a school that is currently top 10 in NCAA D1 ranking and one of the lower players on the lineup came out and hit with us (He was playing 6 on the lineup but he's a 13 UTR). He actually introduced me to the concept of MGRI and referred me to Impacting Tennis' Website.

He used (and is still using) an Ezone 98L heavily customized and I followed suit and bought one, but at that time I already had regular 98's so that's why I'm on this thread trying to figure out the best way to customize them.

@Brando Seeing that your racquets with similar specs to mine have a little higher Twistweight, I might try a setup with similar specs and just redistribute the weight to increase twist weight slightly. Also, as a side note, do you think weight at 3&9 increases spin or decreases spin? This is kind of a question for @aaron_h27 too because this TWU article suggests that spin increases if lead is added at 3&9 (higher TW) unless you are making contact in the bottom half of the racquet (which may well be where most pros hit, I'm not sure). Do you guys feel it increases the launch angle or decreases? I'm just curious (last question I swear).

Thank you for all the help so far by the way @Brando and @aaron_h27

I couldn't answer this question any better than @aaron_h27 does in his post #425. The right TW for you really does depend on 3 things: your play style, the other specs of your frame, and how often you tend to hit vertically off-center. So I like your idea (boldened above) of adding just a bit of TW at a time (maybe just a gram) at 9&3 to your TGT348.1 and seeing how it feels. I'm a big believer in using minor tweaks to find your huckleberry. (And @aaron_h27 is also right that these boards are precisely the place to ask questions of other players. We're all learning from one another. Hells, in my last post I just learned yet another thing from @Irvin, who schools me all the time!)

I'll only add one thing to consider. It might not be so bad to play your pro stock with a 13tw for a bit. It might just alert you to how often you hit off-center, such that it teaches you how to hit the sweetspot more often. This might improve your shot-making in ways you can't yet imagine. Indeed I've noticed something about good players who first learned on the old woodies with their tiny hoops. They're more precise, and so, have a far lower error ratio, even against younger players.

 

[Circa 1762]

Well, I commented up thread when the Vcore 98 Tour was released that it had a 21.0 MgR/I stock, and I just got a (wildly out of spec) Pure Drive demo that also has a 21.0 MgR/I stock, which got me thinking…

@Brando do you think a player’s ideal RW and/or MgR/I depends on the type of racket they’re using, or more accurately their groundstroke form with a racket? For example, say a player has a Percept 97D (lends itself more to flat hitting) and a Pure Aero (lends itself more to spin hitting to control the higher inherent power, Mannarino notwithstanding). Is that player’s “ideal” RW and/or MgR/I going to differ between those two rackets, assuming that the player does in fact modify their form somewhat depending on which racket they’re using?

 

[aaron_h27]

I'm playing some of my most enjoyable tennis with a Yonex SV 95.

Specs : 342g, 7 pts HL, 328 SW, 161 RW, 20.95 MGR/I

I have a one handed backhand, eastern forehand. I'm a rec version of Federer. All court game. This spec really compliments my game style. I am 5'7 so the RW is right on spec with my height. Grateful for @Brando giving us this thread. It has helped my game.

 

[Brando]

Well, I commented up thread when the Vcore 98 Tour was released that it had a 21.0 MgR/I stock, and I just got a (wildly out of spec) Pure Drive demo that also has a 21.0 MgR/I stock, which got me thinking…

@Brando do you think a player’s ideal RW and/or MgR/I depends on the type of racket they’re using, or more accurately their groundstroke form with a racket? For example, say a player has a Percept 97D (lends itself more to flat hitting) and a Pure Aero (lends itself more to spin hitting to control the higher inherent power, Mannarino notwithstanding). Is that player’s “ideal” RW and/or MgR/I going to differ between those two rackets, assuming that the player does in fact modify their form somewhat depending on which racket they’re using?

Hi, @Circa 1762. The better an amateur player’s form (i.e. the more languid their kinetic chain), the more a racquet’s RW determines its coming-through. Conversely, the tighter and more rigid their form, the less weight distribution plays a role in how laggy the hoop comes through vis a vis the handle because the arm and the racquet are acting less as a loose double pendulum than as a rigid or semi-rigid unit guiding the racquet through (which not-incidentally steals energy from a player’s kinetics).

That said, if my theory is right, then the better their form and the more likely the player will find their best RW within a 5-point range per the length of their arm. Will the racquet have an effect on this? Yes. But not enough to take one’s best RW out of range. That is, multiple ratios of weight, balance, and swingweight can bring you within your best RW range. The challenge is: A) finding a frame with (or modding one to) your best Big-3 combo; and B) finding one that also has your favorite unmoddable specs of beam width, string pattern, and head size.

Let’s say you find both a spin and a control racquet with all the above qualities. They could certainly play equally well for you if you’re good enough to adjust your form to play each on its own terms. But if these frames were the Pure Aero and Precept 97D in your example and if they were both on-spec (154 vs 166rw) and your recommended RW range was, say, 164-168rw, my theory says the Precept would come through noticeably more naturally for you than the Pure Aero.

 

[InTheValley]

@Brando @Irvin and other experts.

I apologize as I'm sure this was already answered many times but I just can't get my head around it yet

If, for example, I have a lever that moves with a constant torque, power, speed, everything... and I attach to it two different racquets, one at the time - they both have the same SW but different RW.
So, will they have a different angle with the lever at same points along their swingpath?

Intuitively, it seems to me that no - a racquet is not a flexible object (at least not during a swing) like a whip so as long as SW is the same the weight disrtibution shouldn't matter but I'm sure I'm missing something so if you could explain in non very physical terms it'd be great!

In this quote:

The longer your arm, the faster it’ll bring the racquet head through, causing it to pivot forward to meet the ball too soon and at too sharp an angle. So taller players prefer frames with more hoop-lag so as to meet the ball in front with a stable (open) wrist. Weight closer to the tip and/or tail (polarizing weight) slows down the hoop so as to increase that lag for longer arms. For shorter arms, the racquet head comes through slower, the hoop more naturally lagging the handle. These players then prefer lower recoil for increased racquet head speed with less lag.

I don't understand why is it RW and not SW? The racquet attached to the lever (arm) at the axis of SW (or very close to it if we want to be extra accurate) but definitely not at the balance point....again, what am I missing?

I do understand why RW would matter significantly when the racquet meets the balls (hence the other name of it - hitting weight?) but just can't get it why it'd matter for the swingpath better than SW...

 

[Irvin]

If, for example, I have a lever that moves with a constant torque, power, speed, everything... and I attach to it two different racquets, one at the time - they both have the same SW but different RW.

Inertia (SW and RW) is not dependent on torque, power, or speed. Everything now is a different store. I = mr2

So, will they have a different angle with the lever at same points along their swingpath?

Yes

 

[InTheValley]

Inertia (SW and RW) is not dependent on torque, power, or speed. Everything now is a different store. I = mr2

SW (rotational inertia) is not dependent, but a measurement of how much torque is required to accelerate the racquet, correct?
What I said is that I theoretically attach two different racquets to a lever that operate with a constant torque.

Yes

Would you mind to elaborate?
Do you mean that the moment of inertia at the axis of attachment to the lever (SW) is a more accurate measurement of acceleration of the handle while the moment of inertia around the balance point (RW) is a more accurate measurement of acceleration of the balance point? Which I mean to say, two racquets with same SW and different RW would have the handle excatly at the same points along the swingweight but the balance point of the racquet would be at different points due to different RW?

 

[tele]

I do understand why RW would matter significantly when the racquet meets the balls (hence the other name of it - hitting weight?) but just can't get it why it'd matter for the swingpath better than SW...

As I understand it (I have no training in physics aside from a year of intro courses in college, in which we which did not spend a lot of time on rotation), hitting weight and recoil weight are not the same measurement, nor is hitting weight in the center of the racquet face directly proportional to recoil weight given the same swingweight and static weight. Hitting weight changes depending on the distance from the balance point, whereas recoil weight is a fixed value for a racquet with given specs.

 

[Irvin]

SW (rotational inertia) is not dependent, but a measurement of how much torque is required to accelerate the racquet, correct?

SW is inertia and for a tennis racket then measurement unit is kg * cm2. Inertia is a rigid body’s ability to continue in motion or no motion. Any amount of force will accelerate a tennis racket unless otherwise constrained. An IMU (Inertia Measurement Unit aka SW machine) applies a known force to a racket to put the racket in motion. The SW machine then measure how fast the racket accelerates. The faster the racket accelerates the lower the inertia. The slower the racket accelerates the greater the acceleration.

Would you mind to elaborate?

Suppose you had 2 clear disks with different radii, and you draw a straight line from the center to the outer perimeter of each. If you rotate the 2 disks at the same rps the point at the outer tip of the longer line would travel faster. If the 2 disks were concentric the lines would move around at the same speed.

EDIT: if a clock showed it was 12:15 and both hands rotated around at the same speed, even though the minute hand is longer, the angle created by the hour and minute hand would never change.

 

[Irvin]

Do you mean that the moment of inertia at the axis of attachment to the lever (SW) is a more accurate measurement of acceleration of the handle while the moment of inertia around the balance point (RW) is a more accurate measurement of acceleration of the balance point? Which I mean to say, two racquets with same SW and different RW would have the handle excatly at the same points along the swingweight but the balance point of the racquet would be at different points due to different RW?

The MMOI of a racket is measuring a rackets ability to accelerate around it center of mass. The farther out you go from the COM the harder it is to accelerate the racket.

So the lever is not the SW. SW is the measurement of MMOI + mass times distance squared to the COM. That distance is the lever not the SW.

 

[Irvin]

SW = RW (MMOI) + mr^2 (mass times distance squared to COM)

mr^2 is the lever. The shorter the lever the lower the inertia or SW.

EDIT: Actually r is the lever length, and mr is the torque you’re applying. The longer the lever, the greater the torque needed to accelerate the rigid body or racket.

 

[InTheValley]

Suppose you had 2 clear disks with different radii, and you draw a straight line from the center to the outer perimeter of each. If you rotate the 2 disks at the same rps the point at the outer tip of the longer line would travel faster. If the 2 disks were concentric the lines would move around at the same speed.

EDIT: if a clock showed it was 12:15 and both hands rotated around at the same speed, even though the minute hand is longer, the angle created by the hour and minute hand would never change.

But the example I gave doesn't include levers or racquets of different lengths...

Anyway, let's get back to tennis and let me ask you this -

Racquet A - mass: 300g, balance: 32cm, sw: 300, rw: 155
Racquet B - mass: 300g, balance: 30cm, sw: 300, rw: 180

Which one is harder to swing?
Which one feels more like dragging the hoop?
Which one it takes more energy to get the hoop moving when swinging from the handle?
Which one's hoops will come through faster when swung the same?
etc.

According to what you're saying (if I get it right, excuse me if not) and what all this thread is about - Racquet B is the answer to all of the above questions, right?

But it doesn't make sense for me, because as I understand it, Racquet B would be the answer if we tried to rotate the racquet around its balance point but when we swing the tennis racquet, we rotate it around the axis where the SW is measured (give or take) so given that the two racquets above have the same SW - then the answer should be: no difference.

So what would be the answer and again, what am I missing?

 

[Irvin]

Anyway, let's get back to tennis and let me ask you this -

Racquet A - mass: 300g, balance: 32cm, sw: 300, rw: 155
Racquet B - mass: 300g, balance: 30cm, sw: 300, rw: 180

Which one is harder to swing?
Which one feels more like dragging the hoop?
Which one it takes more energy to get the hoop moving when swinging from the handle?
Which one's hoops will come through faster when swung the same?
etc.

According to what you're saying (if I get it right, excuse me if not) and what all this thread is about - Racquet B is the answer to all of the above questions, right?

Racket A

If you place a weight on a stick, the farther that weight is attached the more torque (m) you have. Racket A has 32*300 or 9,600 gcm of torque. Racket B has 9,000 gcm of torque.

EDIT: Not sure what you mean though by when swung the same.

 

[Irvin]

But it doesn't make sense for me, because as I understand it, Racquet B would be the answer if we tried to rotate the racquet around its balance point but when we swing the tennis racquet, we rotate it around the axis where the SW is measured (give or take) so given that the two racquets above have the same SW - then the answer should be the no difference.

Yes Racket B would be the answer if you rotated the racket around the COM axis. What you’re missing is the difference in balance.

 

[InTheValley]

So what's the point of measuring SW then, if we have two racquets with identical SW and they don't feel and don't actually swing the same from the handle?

 

[InTheValley]

Oh and you said Racquet A - but according to the theory of the OP, it'd be Racquet B, no?

 

[tele]

So what's the point of measuring SW then, if we have two racquets with identical SW and they don't feel and don't actually swing the same from the handle?

according to the only paper i found(did not look that hard) published in a journal on the subject, sw has the biggest impact on racquet speed.

However, balance (and the mass distribution that caused that balance to be different) should theoretically also impact the way a racquet comes through when the arm decelerates before impact. the idea is related to the way a *physical pendulum* behaves and the mgr/i ratio. afaik, in your example, racquet A should come through contact more quickly because its mgr/i value is higher due to the higher balance.

 

[Irvin]

So what's the point of measuring SW then, if we have two racquets with identical SW and they don't feel and don't actually swing the same from the handle?

Let me think about that.

 

[InTheValley]

according to the only paper i found(did not look that hard) published in a journal on the subject, sw has the biggest impact on racquet speed.

However, balance (and the mass distribution that caused that balance to be different) should theoretically also impact the way a racquet comes through when the arm decelerates before impact. the idea is related to the way a *physical pendulum* behaves and the mgr/i ratio. afaik, in your example, racquet A should come through contact more quickly because its mgr/i value is higher due to the higher balance.

Can you please post the link to the paper?

 

[Irvin]

Oh and you said Racquet A - but according to the theory of the OP, it'd be Racquet B, no?

By OP do you mean the Original Post #1 or the Original Poster Brando?