Hi guys, Just bought my N90. Unfortunately after for about 5 minutes( Just warming up) of smashes and lobbing, My strings broke, it broke when i did a smash. i was using all my strength When i cut off the string to look at the racket, i notice a hairline crack at 12 o'clock position around a grommet. I will post the picture later when i get home.. just asking, if i were to use the racket again and restring it at 25 LBS using Bg 65, will it collapse? & do you guys know the reason why it cracked? i was using 27 LBS bg 66 which is 2 lbs above my normal tension.. but it wouldn't crack after 5 minutes right? or was it due to not using it for so long that caused it.. ( i bought from a person who has used it) thanks Loads, Zslasher.