Category Archives: Technology
Time is Catching Up!
Most products that we are familiar with have a window of opportunity; we will call it that. The same holds true for tennis racquets as for cars, refrigerators, washing machines, et cetera.
What I want to talk about today is a racquet that was way ahead of its time, and now time is catching up. The racquet is the Head MXG series, specifically the 98 sq. in. player-style thin-beam racquet.
If you’re wondering why we are bringing it up now, after all these years, the answer is simple: the concept and execution are good and deserve recognition!
The important component, and the one that probably kept this racquet from being highly successful, is the Magnesium throat. That is the silver thing that connects the shaft to the head of the racquet. Most racquets have a similar component, typically carbon fiber, and normally not shiny.
However, the real performance component of this magnesium throat is the length of the ten (10) center main strings. These ten (10) strings are nearly the same length, adding consistency to every shot and a more uniform string bed stiffness.
We have a few of the MXG 98s if you have never seen one and are in the neighborhood; stop by. You can tell us what you think about it.
Strring Bed Stiffness + Effective Stiffness
Racquet Quest lives by numbers, and these are two (2) of the most important.
This short video will, we hope, help explain why they are important and how they can be used to enhance the player’s performance, and that is “consistency”!
Racquet Quest has several different stringing machine models, and we evaluate different setups on each. It is clear that a “reference” tension across different machines will produce different string-bed stiffnesses.
Take a look at the following video and let us know if you think SBS (string bed stiffness) needs to be the new “reference tension”.
Wilson Defyer Pro 98 v1.0
The Wilson Defyer product release is one of the most unusual and talked-about releases in a long time!
The initial prototypes were “Python”; the next iteration was “Redline”; and the newly released, and final, version is the “Defyer”.
The Defyer is available in 98 and 100 square inch head sizes. The string pattern is 16×20 with spacing that allows for a broad range of string bed stiffnesses to suit most play styles.
The head shape and geometry are familiar; however, there is some “sculpting” going on that adds something to the overall appearance.
While appearance is important, the real stuff is in the numbers, and we have those right here…
After you go through the numbers, stick around for some additional highlights that may go unnoticed.
| Manufacturer | Wilson |
|---|---|
| Racquet Model | Defyer Pro 98 v1 |
| Reference Tension | 56 |
| String | MonoGut ZX Pro |
| Machine Used | True Tension Pro |
| String Bed Stiffness - RDC | 47 |
| String Bed Stiffness -FlexFour | 61 |
| Strig Bed Stiffness - SBS | 51.7 |
| String Bed Stiffness - ERT | 33 |
| Racquet Flex, RDC | 65 |
| Racquet Flex, FlexFour | 51.5 |
| Racquet - In Plane Stiffness | 474.4 |
| Weight, Grams | 325 |
| Weight, Ounces | 11.46 |
| Balance, mm | 327 |
| Balance, Inch | 12.87 |
| Length, Cm | 68.7 |
| Length, Inch | 27.047 |
| Head Width | 9.80 |
| Head Length | 12.76 |
| Head Area, cm2 | 633.7 |
| Head Area, Sq. Inch | 98.2 |
| Beam Height @ Grip, mm | 22.5 |
| Beam Height @ Mid, mm | 23.8 |
| Beam Height @ Tip | 22.5 |
| Beam Width @ Grip, mm | 18 |
| Beam Width @ Throat, mm | 13.8 |
| Beam Width @ Mid, mm | 11 |
| Beam Width @ Tip, mm | 13.6 (w/Bumper Guard) |
| Number of Main Strings | 16 |
| Number of Cross Strings | 20 |
| Ratio | .614 |
| Main String Grid Inch/mm | 7.56/192.2 |
| Cross String Grid Inch/mm | 10.41/264.4 |
| Density (% of head filled with string) | .768 |
| Average Cross String Space | .520 |
| Average Main String Space | .453 |
| Dynamic Tension, Kp, ERT | 33 |
| Dynamic Tension, Lbs/in | 184.57 |
| First Moment, Nm | .819 |
| Polar Moment | 333.0 |
| Torsional Stability | 16 |
| Swing Weight, Kg/cm2 | 317 |
| Swing Weight, Ounces | 11.18 |
| Swing Weight Calculated | 347.5 |
| Power, RDC | 54 |
| Control, RDC | 44 |
| Manueverability, RDC | 74 |
| Power, Calculated | 2044.1 |
| Head Points | 5.20 |
| Head Weight, % | 47.6% |
| Center of Percussion | 20.9 |
| Dwell Time, ms | 6.83 |
| Efective Stiffness - lbs | 27.3 |
| K, Lb/In | 150.64 |
| Recoil Weight | 151.88 |
| Twist Weight | 233.42 |
| End Weight | 134.4 |
| Tip Weight | 194.4 |
| 9 O'Clock | 97.4 |
| 3 O'Clock | 94.8 |
| Butt End | 137.4 |
| COF, Main | .382 |
| COF, Cross | .315 |
Something with tennis racquets that is important to us is “serviceability”. The Defyer, like most Wilson racquets, has a nice grommet system that protects the string from “court contact” damage, and is “aerodynamic” in shape.
The grip pallet system is another matter, however, and makes grip size and shape modifications difficult, if not impossible. So, when you are making a purchasing decision, be sure you are choosing the correct grip size. This pallet system is not unique to the Defyer, but the Defyer is in the category of “customizable” racquets. Don’t plan on much grip customization!

Racquet Quest, LLC


