Discussion in 'Racquets' started by Ashley D, Feb 18, 2013.
Anymore thoughts on points 2 and 3?
It all adds up. I think once the frame is moving, these small differences get amplified. In top spin shots, the ball often exits from the edges, so they are very important. That is why everyone who can tolerate the stiffness says that the PD gives free power.
Above 68 may be diminishing returns though.
That seems to be a parallel battle you are fighting. Player should not figure in such discussions. In many cases, the racket makes the player. The PD made Nadal and Roddick, and the PS 85/90 made Sampras and Federer. And also racket analysis has always been done without considering the player. The player finally chooses and modifies one of them. And then on, the racket also shapes him in so many ways.
I think the free power is all in their head, in a blind test the Rad Pro would provide about the same power i reckon.
Your point about hitting near the edges is true for lots of people I agree. I once sprayed the whole stringbed with stencil paint to see where I was hitting the ball, and I hit a lot near the edges. But again I think the power difference is almost negligible.
You are serious about the technical stuff, aren't you?
speed gun tests of pros swinging such sticks?
Again, the human element is introduced, but those on here say it can't be added.
Pros can't swing exacdtly the same every time, and they are human.
By most thought here, it's purely racket, right?
OK, so ...LeeD swings a PD+ and hits a 97mph serve.
MilosRaonic swings a junior racket and manages 110.
By your definitions, a junior racket is more powerful than a PD+.
nope... same pro... or same LeeD... hitting 100 forehands and 100 serves with each of four sticks (varying stiffness, varying swing weight). Stiff/Light, Stiff/heavy, Flexible/Light, Flexible/Heavy.
ball speed measurements taken, stats analysed (averages, correlations, distribution of results, range of results, etc...).
the large(ish) number of strokes should smooth out some of the randomness and variablenss of swing speed/mishits.
Yes, introducing the human element.
Set of balls getting more worn with each hit.
Player get's tired, then get's a second or third wind.
And is this player big and strong? Fast swing speed? Slow swing speed?
Would a player being tested, like Milos, have any bearing on results for a 64 year old, slight and injured/blind LeeD?
OTOH, would the results of LeeD testing apply equally to Milos?
that's the point of testing both a LeeD type and a pro type. what if the results are broadly similar in terms of how much (or little) stiffness matters? surely that tells us something?
What if a Milos and a LeeD type just happen to LIKE the same racket characteristics, and serve faster with it. Human element, hard to get rid of.
And every player between an old injured fart and Milos likes something DIFFERENT! Then what?
Better to find out what works for Milos, and then find out what works for a blind, injured, old, and weak fart....with separated results.
This statement just shows how little you actually understand what's being discussed here. If you think about it LeeD, this is exactly what you would conclude using your own definition and not what you would conclude at all using ours. We're the ones trying to eliminate user variance from the equation in order to avoid incorrect assumptions like the above. You're the one insisting they must be included. You're highlighting the flaws in your own position.
Yes, about 1-2 mph on off center hits. Wow. Definitely worth the tennis elbow.
I feel like I've drifted into an alternative universe.
this thread is, umm, incredible!
people defending this frame or that, making some pretty implausible claims and linking the whole thing to an old Arnie movie..
Anyway, Jack, couple of questions if you have any patience left.
I'm interested because I have just switched to a quite stiff (73) frame with a large head size (104), a reasonable amount of mass (11.5oz) and a sw of 327.
Thing is, I am loving it, having switched from years of player's type frames.
So, are these specs unusual? and if so, why? For me, it seems to have all the benefits of the large head (large sweetspot, easy power) while retaining good plow through and heft (from the mass and sw)
ok, that was question 1
question 2 relates to this post:
I was interested in your thoughts on Intrinsic vs Extrinsic power.
A - You don't measure what they like, you measure ball speed and such.
B* - if results are different then the test is inconclusive. not the end of the world. need to figure out another way to test.
You're not getting rid of the human element with this analysis. You're trying to get real world data on what effect stiffness and swingweight have on real world tennis shots by real world tennis players at different levels. It's the same human, you just change the sticks and see what happens. The difference is you measure it to see what conclusions, if any, can be drawn.
Chillax. I still like the stick i used to play with from when I was ten. You can always play with what you like. It's subjective, but that's not what we're discussing here.
* In reality you'd run the test with several different pros and several different juniors and amateurs and check out the data. See if there is any statistical significance and if so, whether it matters to the actual tennis being played.
Yes, I find the very technical racket stuff fascinating, if I could get a job working on this, I would jump at the chance!
Perhaps LeeD has a point, though not in the way most of us appreciate it. It is player dependent in that a player's own skill level has a lot to do with it.
Even though I've been playing tennis since 1988, I'm still a beginner. I perceive that an APD is more powerful than a Radical, but in reality I'm not getting more power from the APD because it's more powerful, rather I'm getting more power because I'm swinging faster and employing more top spin for control.
So the question remains: what if i swung the Radical just as fast and with just as much top spin? I'll likely hit an even higher velocity shot than the APD. There's more mass behind the Radical, so it logically follows that the Radical is the more powerful of a racquet -- if you can swing it fast enough and still keep the ball in.
So why do I not just swing the Radical faster? Because I can't keep the ball in play with the Radical. It all has to do with:
I can't handle the higher swingweight
I don't have the confidence to swing it faster
I can't generate enough top spin to keep the ball in
Bottom line: The APD enables me to swing properly, and quickly, and therefore I perceive it as being more powerful.
But it's not. The issue at hand is my own skill.
As I said, those who can tolerate the stiffness find great benefit from it. These guys include Nadal and Roddick. I myself don't like Babs, but that is a different story.
I understand your point, but I would say its the head size and beam width on heir frames that give them forgiveness not the stiffness.
90 Sq. Inch to ___?
Thanks for the all the info. you have been providing, I would like to seek your advice with regards to racquet head sizes.
I've been using a 90 Sq. Inch frame for quite awhile now and would be intending to switch to a larger frame size which would be easier to use but at the same time not compromising my style of play.
Do you recommend switching to a 95 or 98 Sq. Inch frame?
Thank you and sorry for the trouble.
No trouble at all, and I'm sure there are others in the thread happy to offer an opinion as well. I've a hunch about what you like about your 90, but before I continue guessing, which model yonex are you playing, whats your string and tension?
Btw, now that I'm seeing that list of frames put together for Anubis, I cant believe I left the Donnay Gold 99 off the menu. (Doh)
Yeah it's gotten pretty wacky at times for sure. But the fundamentals that I am posting is really nothing new, or incredibly insightful. Just good old Newtonian Physics. Momentum = Mass Times Acceleration is old news!
If you have found a frame that you love, that's awesome, and you are in a select minority here (smiley face) While most of the Volkl ta seems to be about players frames, they've always had quite a diverse line up, with plenty of grannie stick and tweener options as well. Your specs are not all that unusual, and there's been a noticeable increase in quality 100-105 tweeners in the past few years. The 73 ra on the new X-7 is a very scary number to me personally, but the larger head creates a softer string bed, and it's got some decent mass so the sw will help reduce impact shock. One thing we are all contemplating in this thread as a central concept, is what you are calling "easy power". There is a little additional power to be had with a stiff frame, vs a flexible frame of equal sw, but it's likely going to be no more than 1-2 MPH tops, and only for shots hit off center towards the tip and the outer edges at 3-9. Whether that is worth troubling over is something for you to decide. In my mind at least, the little extra juice isn't "free" at all, because it comes at the expense of increased risk of injury and reduced comfort.
I'll answer the question in a separate post, a bit of unraveling to do there.
Yes, all things being equal, a racquet with a bigger head will have more inherent rebound power. I've referenced more detail in my quickie fundamentals post # 119. But the difference is probably less than we imagine. See screen grab provided. But first I gotta mention the the major factors before diving in too deep. Head size contributes to racquet power in a three ways.
1 Higher twistweight. That's fancy talk for stability on shots when you miss the center towards 3:00 - 9:00. If two frames have equal mass distribution in every way, but racquet B has a wider head, then B has a higher twistweight.
2. HittingWeight: When one is attempting to figure out the contribution that twistweight makes to power, hittingweight is a great place to look. It is one of the most overlooked concepts in all of tennis. It is the combined measure of both swingweight and twistweight. The hittingweights for most all commercially available racquets can be found in this link. Also, I'm providing a quote from Crawford Lindsey AKA "TW Professor" discussing this very issue in a similar thread way back in 2008.
3. A longer string creates a softer string bed, a softer string bed deflects more on impact, so the ball compresses less and there is less of the kinetic impact energy lost to ball compression. But the difference in measurable MPHs due to a softer string bed is less probably less than we think it is. When Brody, Cross, and Lindsey Published their book on racquet Physics in 2005, they estimated from .3 percent to 1.0 percent increase in power, for every ten pounds drop in tension. So a 100 mph serve gets a bump to 100.3 - 101 MPH. More recent studies with real players on real courts indicated about a 2 mph increase on average for every 10 pound drop in tension using syngut string.
About The Chart Provided: The comparison is a good one because the swingweights are pretty close to each other in the first three racquets. I could not find a big find snow shoe stick at a similar high sw so had settle for the next closest. You'll notice that it demonstrates (again) that racquet power is predominately about swingweight. I have the PS 85 and the Babolat Y188 just for giggles and to illustrate the point, but more useful is the comparison of the Blade 98 to the NCode 90. Speaking frankly, this is for me the largest cognitive hurdle. I'd have expected a much bigger difference myself. Rather than dismissing the available information, I'm currently trying to make sense out of it. One thing I'm not certain about is whether the testing procedure adjusts for string bed deflection/stiffness, per head size, which would suggest higher tensions at larger heads and lower tension with smaller heads. If that factor was leveled, that would be one way to explain the surprisingly low spread in digits.
Quote 4 : " One of the most over-looked tools on TWU is the Hittingweight Calculator. Hittingwieght is how heavy the impact location behaves when it is hit. It is the actually amount of weight behind impact. Every location has a different hittingweight.Hittingweight is a very intuitive way at looking at racquet power. The situation can be thought of as two billiard balls colliding. On ball is the 57 gram ball and the other is a billiard ball of the location's hittingweight. You will find some racquets up at the tip where the hittingweight is very close to the tennis ball's weight. If it were the same, then for a non-swinging racquet, the ball would come to a complete stop and the racquet would fly off instead. Here is the link: It is just a little pop up calculator. You can also get there from the TWU home page and clicking "Calculate hittingweight at impact location" on the right side of the screen.- TW Professor / Crawford Lindsey, 2008
Quote 5: (Not much discussion directly to the subject of head size, but 100% on target for the topic at large) "Nobad is correct in the sense that increasing racquet speed is always the easiest way to increase ball speed. Let's consider an example. Suppose you have a racquet with a power potential of 40% at the hitting location. The ball is coming at you at 30 mph. You swing your racquet such that the hitting location is traveling at 60 mph. The ball will leave at 96 mph.
Of that 96 mph, 37.5% of the final speed is due to the bounce from the racquet (power potential). The rest, 62.5% is due to the speed of the bounce pad (racquet) from which the ball bounced (from the formula that ball speed = bounce speed + bounce pad speed). For most groundstokes where the racquet is traveling faster than the ball, racquet speed is more important to ball speed than is power potential (which depends swingweight). If power potential is 40%, then every 1 mph you increase swing speed, you will increase ball speed by 1.4 mph. But for a given swing speed, you want to maximize ball speed by having the highest swingweight you can comfortably swing. That's evident by considering what happens if you lower swingweight too much in an attempt to gain swing speed.
As swingweight gets lower you have to swing even faster to get the same speed. So, if instead of 40% we have a power potential of 20% (because we have lowered swingweight so much), then, for the same 30 mph incoming ball speed and 60 mph racquet speed, our outgoing ball speed is 78 mph. To make up the difference of 18 mph we have to swing about 10 mph faster. Perhaps the lower swingweight allows us to do that. But who wants to be swinging that fast for the same result? Accuracy and control go down and shock goes up.
Shock. That's a whole 'nuther' issue. Mass is always better at lowering shock. But even less shock can cause more strain on the arm if you are hitting late because of the extra mass. But on the other hand, swinging faster with less mass is going to blow your arm up too, even if your timing is correct. That's because the change in momentum due to the collision will have to occur by changing your racquet velocity much more for each gram of racquet weight than if the racquet had a greater mass (hittingweight) at the impact point. Momentum is mass x velocity. If you have many grams, each one has to change velocity less than if you only have a few in order to achieve the same change in momentum. Greater change in velocity of the racquet head compared to your hand means greater strain at the wrist.
So, as always, knowing these considerations helps you demo and experiment with racquets to choose the right combination of racquet speed and swingweight for you. If you know what the effects will be of changing variables, you will be able to analyze what is happening and why and then be able to change variables to meet your goals."- TW Professor / Crawford Lindsey, 2008
I am using the Yonex RDS001 90 frame. And I use Signum pro hextreme with a tension of 57Lbs.
So rhs makes a bigger impact than swingweight? I realise ideally I'd swing a heavier racquet faster!
Hi Jack, love your posts, very informative and entertaining. Just thought I'd correct your slip of the keyboard to avoid confusion: Momentum, of course, is Mass times Velocity, not Mass times Acceleration.
Hello again Kaiser,
Doh, good catch.
F = MA,
Force equals Mass times Acceleration.
and also ...
p = mv
Momentum equals mass times Velocity.
I think I swapped the tail ends of those two.
Man, I think we'd all like to do that! The biggest gains (on paper) with regards to increasing power would come from increasing mass, while keeping racquet head speed constant. If you could do that, switching from a 250 gram racquet to a 400 grams racquet results in a 15% increase in ball speed on a 100 MPH serve. So you'd get a pretty big bump up to the vicinity of 115 MPH.
However, its simply not possible to swing a 400g racquet as fast as a 250g racquet. It is reasonable to assume that as mass increases, maximum RHS drops. In a serving motion we are already swinging as fast as we can on both first as second serves. All that really changes if your technique is good is that the second serve has more spin. So, in the serving motion, where you are already swinging for the fences, there is much less room for improvement in serving speed by adding mass. What this all boils down to is that adding mass, might change the feel and timing of your stroke, but its not likely to add any significant increase in power. Since we know that the speed of the tip of the frame is always traveling about as fast the serve, the easiest way to get a 1% increase in serving speed, is to simply swing the racquet 1% faster.
In a ground stroke however, players often are not swinging as fast as they can on every stroke. You might unleash your most fierce FH when your guy is rushing the net and you need to nail one at his feet. But swinging as fast as you can, on every FH and BH is just going to produce a whole lot of unforced errors.
So on groundies, its a whole nuther deal, because we are often "dialing it down" intentionally so to speak to maintain consistency, so adding mass is much more beneficial. That's because players are not swinging for the fences on every ground stroke. What that boils down to is the opportunity see a substantial boost in power while maintaining the same timing that you are accusotmed to. It's the old adage, play with the heaviest racquet you can swing comfortably in its most basic sense.
You might feel differently about the added mass deep into the 3rd set in a tough singles match. But I think that also explains why pro doubles players are playing with much heavier frames than the singles guys. Hitting the ball half as often leaves you with less energy expended, so tiring late in a 2nd set breaker isn't a factor in the same way.
Marcus I see your most recent question, I'm out the door for a bit but will return asap - Jack
Natural Gut....buy it, string it, love it
Jack just nailed a huge point that everyone should pay attention to.
You have to find the realistic weight where you can hit your serves comfortably without any stress AND also hit your groundies deep and with some weight. So the factor of head speed and SW comes into play big time. For me, I lowered my SW a touch to the high 320s to benefit my serve. My groundies can handle a 340ish SW, but my serve suffers.
So there is a happy medium you have to find. This is where the other key comes in - timing. Hitting the ball out in front will give you a lot of easy power. I had a pro tell me that all he cares about in the first set of a match is hitting out in front. Nothing else really matters to him. This also allows you to hit bigger with a little less SW.
So the serve really benefits from head speed. It is key as Jack is saying. The groundies benefit from SW and timing.
The way to figure out your ideal SW (in my experience) is to get it to where you can always hit your groundies out in front and you don't feel like the racquet is lagging. Start lower..maybe 320 or so..whatever. You can always add lead. Your serve will benefit.
The reason the pros can use such a high SW is because they gradually add lead over time (one direct quote about this came from James Blake who gradually added 2 grams). The more you play, the stronger you get, the more you can add 2 grams or so every few weeks. Imagine playing the same racquet as a kid like Murray did. His pt630 had a stock SW of ~ 330. He is probably in his teens using that stick..then he gets older, stronger..every few months his team is adding lead to his stick. He is getting in better shape, lifting, playing 6 hours a day..etc. It is no surprise in his mid 20s he now swings a racquet with a massive 365+ SW.
Most of us play around 10 hours or so a week..maybe a little more or less. In my experience, it will be a very gradual process to where you would add lead. Maybe you won't change anything for a year..who knows. Maybe you never change at all.
Anyway I posted this because a lot of people (including myself) have tried these massive pro SW setups and while groundies are a blast, the serve breaks down in matches for most people. It takes a ton of hours and time to get that huge SW setup.
So it is better to start lighter and don't add lead unless you are finding yourself way out in front or too early too often. The power is there with the lighter sticks too, it is just more about head speed and timing.
No worries will be waiting for your reply.
I read this and thought of you.
Oh Hey PP, long time no see
I've lurked around in that thread from time to time, but I've chosen to enjoy the show from the cheap seats with my popcorn and milk duds. Almost everything I would contribute there is in direct opposition to the group think that seems to be going on.
I'm a bit strategic about picking my spots these days. I'm happy to provide info when there is a genuine curiosity, that is more fun than a box of kittens. But getting into extended heated debate with folks who don't really want their assumptions challenged is not a good use of my time.
Having said all of that, Babolat is known for producing very stiff frames, but there's some real lower flex gems hidden away on pages 3-4 of the menu. That black and gold Pure Storm Limited is pretty sweet, and the specs are Pro Stock range ... sw305, flex62, 8 points head light, and a leather grip to boot. That's a sweet hit and a great platform for customization right there.
Once again, a player hit with power, the racket is only a tool.
A weak player cannot hit with power even with a PDR.
A strong hitting player will hit hard with any racket.
What?! Rebel 95 is one of most powerful sticks around - more power than light chick sticks. It has good long mains and decend weight - serves just bomb with it
Are you sure BLX Team flex is in the mid 50's?
Seems the BLXBlades I tried are very stiff, almost APD stiff.
Argument settled everybody case closed, these racquets will generate the exact same power for you.
The WILSON Six.One Team BLX Tennis Racquet has a flex of 64 not mid 50's are you talking about a different racquet?
This is an old thread from Feb 2013 that just got bumped back up recently. I doubt Ashley will reply, it's probably way off her radar, and typically hangs in the technique forum more often than here. However, I'm guessing she is talking about the BLX Blade Team as described in the opening post. That racquet does indeed have a flex of 53.
This thread is really interesting, but I am surprised how some people are convinced that current take on what matters is somehow definitive and correct, when it is so different from what was the "science" few years back (if I am reading some posts correctly).
Is it possibly that we do not measure aspects of the strokes, which are relevant to perceived "power"?
Let take another hobby of mine, hi-fi. While I personally use solid state amp and CD player, to my ears valve amp and record player often sound more like real music (ok, expensive ones do and I listen to classical), although on most supposedly relevant measurements, solid state and CD players are better than valve and vinyl.
I am 4.0 OHB and SWF baseliner, so I can not claim real understanding of high level tennis.
However I have been testing dozen rackets a year for a while, so I have some idea what suits me.
I play with Head Prestige Pro YT and with Dunlop Biomimetic 200 Lite on my off days (post my wine and cigar sessions ).
However, I played best (i.e. winning more) with Babolat APD. I guess everyone knows why I could not continue: pain in my elbow.
Now, my tennis partner claimed (and I felt the same) that my balls were travelling faster towards him, so he was struggling to get in position to hit a reply.
I am not sure if by power we mean just higher shot speed or what is referred to as heavy ball as well.
I know it is not scientific and it could have been other factors (spin, trajectory, who knows?) but for whatever reason it at least partially explains why Babolat APDs are popular with so many people at various levels.
If I could, I would play with APD, because what matters is winning and enjoying tennis (winning is part of enjoyment; in my book anyway) and not using what pros use (whatever PT57A etc. is), even if it does not really help your game.
I am not shy of contradicting myself and neither me nor my partner could generate any pace using Babolat PD ( dark blue one, with low swingweight) although it is even stiffer than APD. Go figure.
I think some people mentioned being able to swing freely when referring to APD, which was my experience.
So it might be that at level 5.0 and higher, fit players can generate enough RHS using flexible, heavy, high SW rackets to produce sufficient spin to keep ball in and gain other benefits of those frames, but how relevant it is for majority of club hackers like me?
thanks and regards,
I"m low 4.0.
I hit the ball harder with my 60 flex Dunlop4DAero300s than I do with my 69 flex DunlopAero500's weighted to close to exactly the same specs.
The stiffer racket CAN hit the ball harder, if you take out the player from the equation.
BUT, if you add the player, the confidence gleamed from the softer racket allows the player to hit harder with the SOFTER racket.
First flat serve favors stiffer racket.
After than, it's more a confidence issue than kinetics, and the PLAYER can swing consistently fast with a racket he feels comfortable hitting with, regardless of what it is.
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