Badminton Guide channel had just release their review of Axforce 100 on Youtube. 1 thing which thickle me is they provide stiffness rating on long handle mode & short handle mode. Interestingly both resulting different number. If the object is the same, how holding the racket at different position could affect the stiffness of shaft? Is it really possible or logical?
I'm guessing theoretically, if you grip the racquet higher it will feel stiffer as theres less distance for vibrations to travel. Personally, I do think its a neglible difference though.
Yes and no. No it will not change the stiffness of the shaft, it’s not possible to change the physical properties based on where you hold it. It can feel stiffer, but when swinging the arm at the same speed, the head will be traveling faster when holding it further from the cone, which could effect how it flexes in a functional way. With so many more materials being used in modern rackets that behave differently, flex differently, rebound differently, etc. I’m not really sure their actual methodology? Because even in a moving scenario depending on the materials, they would flex differently at different racket head speeds, not necessarily in a linear manner. Nd the head may flex differently at different spots than the shaft. there are ways which it would bring this as a result though. The security of the mounting mechanism. The actually flex of the handle, which is possible but not probable at the force exerted without inertia. Lastly when mounting, even though secure, there is a reduction in flex at or near the cone cap depending on where it’s secured for measuring, which again wouldn’t happen with a human hand, except if it feels stiffer because the racket head is moving slower therefore not flexing as much. I hadn’t watched their videos until just now, but since Yonex’s Precision Scan does a pretty good job of detecting headweight, weight, swing weight, functional swing weight, etc. I’m not sure how they claim no machine does an accurate job. If using that machine you at least have a consistent point of reference for how rackets compare to each other. But they are still including this info and the caveats about it on the swing weight slide.
I started a discussion about their stiffness measurements a few years ago when the channel was new. https://www.badmintoncentral.com/fo...ured-racket-specs-including-stiffness.186447/ Unfortunately my conclusion then was and still is that their stiffness measurements are flawed and pretty much useless. Like for example I recently saw that they measured the Astrox 77 pro as stiffer than the 99 pro which as far as I'm aware is completely contradicting what everyone who I have ever seen test those two rackets have said. Yeah this has always bothered me too since they started including their own swing weight numbers which I believe they don't actually measure with any of those machines but calculate in some way. I have never heard anyone else say that those Yonex, Babolat, Victor etc machines that measure swing weight can't be trusted. At least not for relative comparison on the same machine. I appreciate their effort and they do provide some good data that I assume can be trusted but unfortunately the stiffness rating I would ignore or at least take with a very big pinch of salt. Is there any other source nowadays for stiffness measurements? Other than these guys or badmintonracketreview which I don't trust either.
Yes, the longer the lever the greater the force, however it cannot change the stiffness of the shaft. It is static.
Its pretty much understandable if we swing it as the further the axis from the head, which is why smashing full force from the end of the grip always feel so amazing. The problem is the way they do measurement which by putting a standard weight & see the displacement of the head position. With that, holding it with long or short grip wont be matter right? Also with today improvement where manufacturer also trying to control not just the stiffness but also the flex location, i doubt putting weight on the head still a valid way to measure stiffness. I can only imagine a swing machine + ultra fast camera to simulate the same swing speed & catch the displacement when swinging would be more accurate, but that would be much more expensive rather than just simple iron chunk.