Swingweight comparision -- seems something is wrong

[corbind]

These two sticks have very similar specs. Same weight, 1 point difference in balance, but the swing weight (SW) is different by 14 points! That does not make any sense to me. Can someone explain? I could see if the stick weights were way different or the balance point....

Prince EXO3 Tour 100 18X20 -- http://www.tennis-warehouse.com/Prince_EXO3_Tour_100_18X20/descpageRCPRINCE-PEX320.html

Head Size: 100 sq. in. / 645.16 sq. cm.
Length: 27in / 68.58cm
Strung Weight: 11.6oz / 328.85g
Balance: 7 pts HL
Swingweight: 322
Stiffness: 52
Beam Width: 19mm / 20mm / 19mm /
Composition: Graphite
String Pattern: 18 Mains / 20 Crosses
String Tension: 50-60 pounds


Boris Becker Delta Core London Tour -- http://www.tennis-warehouse.com/Boris_Becker_Delta_Core_London_Tour/descpageRCVOLKL-BBDCLT.html

Head Size: 93 sq. in. / 600 sq. cm.
Length: 27in / 68.58cm
Strung Weight: 11.6oz / 328.85g
Balance: 6 pts HL
Swingweight: 308
Stiffness: 55
Beam Width: 19.5mm / 19.5mm / 19.5mm /
Composition: Delta Core / Carbon-Graphite / Fiberglass
String Pattern: 18 Mains / 20 Crosses
String Tension: 50-60 pounds

 

[SystemicAnomaly]

Two words... weight distribution. Up until 9 days ago, I was under the impression that the static weight and the balance point were the only factors that determine the swingweight (SW) of a racket. (Actually, holding the racket at different positions would also affect SW, but that's not what accounts for the published differences in SW). SW is a measure of rotational inertia (which is dependent on the distribution of mass). Check out the following thread on this subject (take a look at both pages for more insight):

http://tt.tennis-warehouse.com/showthread.php?t=417172
.

 

[spaceman_spiff]

You can get a visual representation of the weight distribution with the TW hittingweight comparison tool.

http://twu.tennis-warehouse.com/cgi...3|Boris Becker|Delta:Core:London:Tour|RCVOLKL

http://twu.tennis-warehouse.com/cgi...320|100|Prince|EXO3:Tour:100:(18x20)|RCPRINCE

You can see the BB has a couple more grams in the bottom four locations but less weight in the center and top locations. That's why it has a lower swing weight.