Hi, i just made a little experiment on racquet balance point. I took two easy mesure, 1- total lenght 2-balance point from buttom.I tested four racquet that i have in my opssession, four very differents racquets: yonex AT-700 3u (270$ cad) Kason carvel U-3 (83$cad) Babolat Satellite Pulsar (114$ cad) Yonex Mp 33 2u (about 150$ i think) so here's the result *note that all the racquet were taken as is, with string and grip. Racquet |lenght(cm)|balance point(cm)|%bp/lenght| 1-At-700 | 67,3 | 29,6 | 43,98 | 2-Carvel | 67,5 | 29,6 | 43,85 | 3-Pulsar | 66,4 | 28,1 | 42,32 | 4-MP-33 | 66,3 | 28,5 | 42,98 | when i look at these result is there about 1% difference between every racquet. And i think the most important factor is the weight of the grip. So this lead me to think that the balance point is no big deal arn't it. I'd like to have an input on a supposed hear light racquet like the nanospeed series to see if these is a difference from what i measured. Also, i'd like to have feedback from someone who know the physics and can tell if this little difference in Balance can really make difference. So far my tought on all these racquet caracteristics are that this is just marketing. the four racquet listed are from differents prices range and they all seem to perform as well. And for me the most important factor is the string tension, a pound make an huge difference. Finally my advice for everyone looking for a new racquet: take a racquet that has the good weight (cause you can't change this value) from a underground compagnie. this way you'll be able to spend the rest of your money experimenting the good string tension, cause that what really make the difference. discuss...
of course the specs listed on the Yonex sites are off. In fact, the specs contradict each other from one yonex site to another. For example, AT 800DE is listed as stiff but in reality, it would be flexible to medium flex. Also, I don't think experimenting with string tension is such a good idea for a beginner. 20 pounds generally seems to work with most people and when they get comfortable with the racket and the game, then they can experiment.
If you want to measure rackets, I would strongly suggest you to get them in original new condition where there is no strings or extra grips on it. The weight of the strings would change the BP a lot since it's placed at the end of the racket (precisely speaking, the racket frame). Take an extreme example, where a 0.80mm string certainly weights a lot, while a thin string like 0.65mm, would weight much less than the first one.
Definitely agree. Even though just several grams, but it counts as a big percentage as the racket itself is very light as well. Yonex list its spec based on the brand new racket (no extra grip, no string), how they can list spec, without knowing what kinda string and grip the player going to add???
Of course you can change it, you can change it a lot. Method to add weight: Add grip, add string, add lead tapes, etc Method to reduce weight: Remove/change grip, sanding down the handle, etc. Yes, the change is within several grams, but the percentage is huge, especially when you swing it, remember energy = mass x acceleration, a small percentage change in mass can tranfer into great change in energy.
I have to say that I find the idea of balance point of a racquet rather pointless because by adding a grip you will change the balance point. What would be more useful is the absolute head (or frame) weight of the racquet. For example, Yonex AT 800 offensive (head heavy) will be no more manoeuvreable if its balance point is change by adding a grip. Flex is important but there is not agreed standard measure between manufacturers
my 4U AT feels a lot more head heavy than 3U mp99. so head and overall balance probably isnt total ********
sorry lazy but your formula is partially wrong. F = ma F is force measured in N, or newton, m being mass and a being acceleration E, which is energy is measured in J, joules.
balance point matters...but there're catches... I just ramblem a bit: -the problem with your test is you have racket of both different lengths, weights and manufacturers..all matter to how head-heavy the racket feels.. -I firmly believe how much weight there is at the handle is almost irrelative...because you hold your racket at the end the moment of that weight is ~0. when you measure a b.p. however it matters a lot... -the weight you feel when you swing is actually the moment of a racket, the distance of the weight to the suspension point (your grip) times the weight. So the extra 3 grams of grip you add on a racket changes the balance point a lot (moment= distance x weight) because the distance is ~250-300mm. when you hold you arcket at the grip however the change is minimal, because the distance is almost 0..so the moment is as well. -because there're so many factors (weight, length, b.p.) tests are hard to do, and they soemtimes lose contact with the real world...
ok, here it comes..some (small) test of my own, In no way as close as Coolers "yy 2003 measurements". but here it goes: the models+specs: modelweight (g)length (mm)balance(stiffness) woven 6 82 665 283 stiff woven 9 84 675 295 stiff woven 10 89 680 300 extra stiff woven 11 91 680 300 extra stiff woven 12 87 670 291 stiff woven 13 89 675 295 extra stiff lot's of different rackets, the only ones that come close to each other are the 10 and 11... observations: -while the 6&9 are aprox the same weight the 6 feels waaaay lighter (so weight alone says nothing) -while the 9 and 13 have the same b.p. the 13 swings slightly (very slightly) heavier than the 9...whiel the 9 fééls relatively head-heavier -the 10 and 11 differ just 2 gram the 11 feels heavier and slightly head-heavier.. -while the 12 isheavier than the 9 it feels lighter, and moremanoevrable. due to the b.p. and it's length. -the 13 feels heavier and head-heavier than the 12..btu that's pretty obvious -all other omparisons feel too vague, as the rackets are too different. my point being: stats matter, though drawing conclusions is hard..
Benasp, Excellent experiment! I am doing that myself all summer and still haven't find the answer, but I did understand this subject alot better. The balance point from 296 to 281 make the same racket(same U, flex etc.) feel alot heavier. Play with it, then you should feel your wrist hurt more, but your smash should be much harder. You are also correct about the weight of the racket. There is NO WAY to change a head heavy racket to lower the balance point, unless you get a very light (less then 4U) and add lead tapes to the handle. But usually, you made that reacket too hevry to play with. I did that, it took like 8 grams to lower 10 BP. I AM 100% agree with you on the string tensions. Again this is given the rackets spec are the same. I just brought couple of rackets from my own spec, 87 grams + 3 grams strings + 5 grams over grip = 95 grams totoal weight. The balance should be aournd 290. I will use those to test strings tensions, more on that later. I think I agree with you the name brands and all those fancy materials may not make that much difference. But play with Yonex does feel and look good. The question is that worth 2-3 times of the money?
for the one who said to test the racquet plain with no string, i mean that where my point is. The compagnie measure are not the actual playing stats. If a change in the string or grip make BP vary more than the difference between racquet, then this stats is totally lame. But i agree with jerby, the andle don't count in the equation. For the shaft stiffness, it would be cool to have high speed video of stiff and flexy racquet to see the real difference. My theorie on that is that flexible are more forgiving for beginner cause they give a bigger range within the player can make a good stroke. But stiff are more precise when you have acquired the good timing. But again a high speed video would told us if there a real noticable difference.
To say the position of the racket's the center of gravity makes no difference at all to how a racket performs is just ludicruous.
BTW, why are you(benasp) dividing B.p. by length? what kind of figure is it that roles out? From my experience both length ánd b.p. positively effect 'swingweight' hwo ehavy your racket feels when you swing it...shouldn't you multiply, or add them up? also, what kind of grip did you add to your at700 to get a b.p. at 296mm...I thought the at700 was at least 315mm...since it's head-heavier than my 303mm at500...
Just to be anal, Fnet = ma. There are many types of forces and for real world problems, usually more than one force acts upon an object and thus Fnet and F does make a difference Also, I thought work was measured in joules? I was under the impression that Energy could be many formed and thus no particular unit was given to identify it. I could be wrong though ^_^