Saw this off the forum at BBEShop, translated by hand so accuracy might be questionable, but I don't think it will pose much of a problem. Anyway, here goes... Muscle Power: The mos fragile rackets Once in a while we see people complaining here on this forum that they broke their MPs even though it was very new and they didn't string it outside Yonex's specifications. So are they really that fragile? The answer is YES! Muscle Power is Yonex's supposingly revoluntionary design that enhances string unity and reduces tension loss and wear and tear. Although it is true that the MP bumps do live up to their claims, they also weakened the frame by notches. In conventional rackets without the MP bumps, the string rests on the edges of the grommet holes and so the tension is evenly dispersed by the grommet holes and the string. However with the MP bumps, only the midpoint of the MP takes in all the tension, so the collapsing forces acting on the frame are much greater than those without the MP bumps. For this reason MP rackets are far more vulnerable to damage when strung at high tensions. This can be further proved by the lack of use of the MP frame design in Yonex's new racket series such as the Armortec series (which can be strung up to 25 pounds) and the upcoming Nanospeed 7000 (which can also be strung up to 25 pounds).
I have to disagree on this article. This person needs to study more physics. Not to mention this person has wrong thoughts on the NS-7000 as well (because I have NS-7000 here)
I have found some observations from my store and clubs as follows: Most MP88 will crack at 12:00 position of inner frame after 1/2 to 1 year intensive use. 70% MP77 will crack at 10:00 to 11:00 position after 1 to 1-1/2 year intensive use. MP100 would be the racket being dead in most rackets crashing. 1 of MP99 broke when the frame was hitting on the shuttlecork, string tension is only 22/24. I will comment MP is not a durable racket series, but I don't think it is totally related with MP structure. My comment is that Yonex's quality is going down, the more the rackets broke, the higher turnover.
those ex. are due to bad stringing. I've commented before in other thread that it's easier to blame the racket first when broken as errors in stringing aren't visible nor can be trace back to stringer(s).
I agree with Cooler (hey I have to sometimes!), no seriously. Even thought I have just sold my MP99 and MP100 (I have update to AT800 OF & DE), I have had the MP100 since 2000 and the MP99 since 2002. It this was the case, both should be cracked or broken - not so! In my opnion, MP gromments were not discontinued due to pressure on frame, more like cost of psecial gromments - or more likely Yonex wanted to change the design for market purpose. Also noting MP99, MP77 etc are different from MP100, as MP100 didn't feature the special gromment strip like the other others, only haveing special gromments on the bottom of racquet (two either side of T-joint).
