Frame design in Yonex rackets

Discussion in 'Badminton Rackets / Equipment' started by Lao Liu, Jul 16, 2001.

  1. Lao Liu

    Lao Liu Guest

    I cracked my Yonex SP900 sa racket. An odd sound attracted my attention when I mishit a shot on the frame. It cracked. Disappointed to break my faviourite racket for doubles, I found some interesting facts: 1. The crack locates at 12 o'clock right in the top middle of the frame. 2. The crack is across the frame and the edge is clear cut. 3. Recently 3 SP900 rackets, including my, were broken at the same position.

    It is not all bad. I spoken to my local shop assistant, a Yonex retailer, he suggested to send the racket back to Yonex and ask for a replacement, possibly a SPti sa, meanwhile he lend me a SPti sa until my replacement arrived. The pain that I lost my racket now was already relieved.

    I checked my other rackets, clearly a crossing mark exists on the outter surface at 12 o'clock on both SP ti and Ti 10. I wonder there is a perticular reason for it?
     
  2. Gladius

    Gladius Regular Member

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    Its the molding seam of the racket frame. All rackets have it. Its just whether they have been comestically covered or not.

    In some cases, it may actually be better if they are left 'as it is' since machining it down may actually weaken the jointed area.
     
  3. cooler

    cooler Regular Member

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    lao liu, are those 3 broken sp900 strung by the same stringer/shop?
     
  4. George

    George Guest

    It happened to me on my ISO800 SP. The graphite collapsed right at 12:00 and and two more areas collapsed right beside it within 2 weeks. I strung mine at 21lbs cross and vertical. I've been stringing at Lee's for 2 years with my ISO800 SP. Usually 20lbs. cross and vertical but feels a lot like my MP100 at 24lbs. Lee's never mentioned the 2 lbs. difference when I went in for stringing except for once. Won't be back to Lee's for stringing. Will go for the training at Lee's but not for stringing.
     
  5. Lao Liu

    Lao Liu Guest

    As you guessed correctly, yes, they all came from the same shop, but not sure about the same stringer. Would the same tension in both vertical and horizontal directions contributes to this? I have my 900 strung at 22lbs in both directions.
     
  6. George

    George Guest

    I could be wrong but stringing the same cross and vertical tensions over a long period of time could damage the racquet. I remember reading on badmintoncentral that the construction of the isometric series is a two piece process in which at 12:00 it is joined together. Whereas, the MP series is a one piece design, and not joined at 12:00 which makes the frame more solid and withold higher tensions for a longer period of time. Correct me if I am wrong. I remember a stringer told me that a 2 lbs. difference used would enable the frame to last longer.
     
  7. Lao Liu

    Lao Liu Guest

    Good to know the 900 frame is constructed with two pieces.

    Another point: In all my rackets strung with even tension in both directions, the breaks appreare almost always in the horizontal strings not the vertical ones. Does this seem odd considering the vertical ones should be strung 2 lbs lower than the horizontal ones, and even tension would make the vertical ones to break more easily than the horizontal ones?
     
  8. Yogi

    Yogi Regular Member

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    Guys,

    Let us accept the simple fact! Isometric rackets are indeed badly designed. I think someone wrote abt the physics behind a Oval shaped racket.

    I have played with rackets and seen rackets of different kinds but i have noticed that isometric rackets tend to crack at 12 o clock positions and sometimes at the beginning of the flat part of the head that is 1'o clock and 11'o clock.

    As someone stated it is moulded at the 12'o clock position but so are the oval shaped rackets.

    It is just a small design defect when it comes to Iso rackets.

    So let us live with it!
     
  9. Tim Yu

    Tim Yu Guest

    I had two Ti-6's crack in that same position: 12:00
    I tried sending them back to Yonex to replace but they refused.
    Their reasons were 1) Strung too tight & 2) misuse
    I only had it strung at 23lbs and I never abuse my racquets.

    Good luck on getting them replaced.
     
  10. shaun

    shaun Regular Member

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    George, ur asessment about the mp frames being 1 peice is indeed true. As for the difference in string tension b/w the mains and crosses, the reasons are as follows:
    As we all know, an isometric racquet is angular at the top of the racquet....and logically, the most fragile part on the frame of an isometric racquet would be where the angles are. The reason for stringing tighter cross is to help out with the durability in those areas....i forgot why and how...but that was what yo sports explained to me.
     
  11. cooler

    cooler Regular Member

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    High Noon

    look like lot of rackets gotten killed high noon at the OK corral. Who's fault? Is it the weapon maker Winchester Yonex? Lao, george or tim the kids? or the deputy sheriff stringer? Meanwhile, back at the ranch, cowboy cooler had been stringing his and neighbor's rackets since his settlement days of the wild wild west. He hasn't experienced these high noon death before, especially when cooler had strung his weapon at caliber higher than 22. Hey, 22 are kind na good for gophers but not useful against bigger varmits. All of cooler neighbor ranchers have asked and gotten 23 to 26 caliber cartridges before without problem, both rim and center fire kinds too. Very weird, hopefully those darn mystery disease don't get into my ranch. Cowboy cooler have some suspicion but don't want to pointy the fingers as he got no tangible proof. Also, I like it out here at the ranch, nice and quiet, don't want to start accusing and messing around with Winchester Yonex nor the deputy sheriff stringer boys if you know what i mean. Don't want no trouble nor shooting around here.
     
  12. Yogi

    Yogi Regular Member

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    Re: High Noon

    The wild wild west will be proclaimed again by the INDIANS def! Dont u worry abt that.

    That was fun. Either way It is surprising to know u have never come across a cracked racket while stringing.

    Pretty strange for such a big rancher!
     

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