Category Archives: Technology
Power from Head Radical Pro
As with many of the Head “Pro” series racquets, they have been considered control racquets, not necessarily powerful.
We set out to see what kind of “power” number we could get using string bed stiffness only. Obviously, more swing weight and maybe more overall weight would do it, but the Head Radical Pro is already at the top of these specifications.
The following video is a look at our software data.
A Long Head Gravity Tour 98
As a high performance racquet technologies business, we have requests for everything imaginable, some not so imaginable! Long racquets are at the top of the list.
Here is a review of a Head Gravity Tour 98 2025 SMU that is 27.75 inches long/70.485cm. See if you can determine which property is most affected by the length.
You can see the string properties here as data taken on our Questron.
| Manufacturer | Head |
|---|---|
| Racquet Model | Head Gravity Tour 98 2025 SMU |
| Reference Tension | 57 |
| String | MonoGut ZX Pro |
| Machine Used | True Tension Pro |
| String Bed Stiffness - RDC | 52 |
| String Bed Stiffness -FlexFour | 61.0 |
| Strig Bed Stiffness - SBS | 50.6 |
| String Bed Stiffness - ERT | 37 |
| Racquet Flex, RDC | 58 |
| Racquet Flex, FlexFour | 43 |
| Racquet - In Plane Stiffness | 429.5 |
| Weight, Grams | 335 |
| Weight, Ounces | 11.82 |
| Balance, mm | 331 |
| Balance, Inch | 13.03 |
| Length, Cm | 70.5 |
| Length, Inch | 27.756 |
| Head Width | 9.86 |
| Head Length | 12.71 |
| Head Area, cm2 | 633.6 |
| Head Area, Sq. Inch | 98.2 |
| Beam Height @ Grip, mm | 21.3 |
| Beam Height @ Mid, mm | 21 |
| Beam Height @ Tip | 21.5 |
| Beam Width @ Grip, mm | 10.5 |
| Beam Width @ Throat, mm | 10.6 |
| Beam Width @ Mid, mm | 10.8 |
| Beam Width @ Tip, mm | 12.2 |
| Number of Main Strings | 16 |
| Number of Cross Strings | 19 |
| Ratio | .650 |
| Main String Grid Inch/mm | 7.72/196.1 |
| Cross String Grid Inch/mm | 10.25/260.4 |
| Density (% of head filled with string) | .785 |
| Average Cross String Space | .546 |
| Average Main String Space | .464 |
| Dynamic Tension, Kp, ERT | 37 |
| Dynamic Tension, Lbs/in | 206.94 |
| First Moment, Nm | .858 |
| Polar Moment | 362 |
| Torsional Stability | 18 |
| Swing Weight, Kg/cm2 | 344 |
| Swing Weight, Ounces | 12.13 |
| Swing Weight Calculated | 367.0 |
| Power, RDC | 49 |
| Control, RDC | 52 |
| Manueverability, RDC | 57 |
| Power, Calculated | 2096.5 |
| Head Points | 6.77 |
| Head Weight, % | 47% |
| Center of Percussion | 21.44 |
| Dwell Time, ms | 6.492 |
| Efective Stiffness - lbs | 27.42 |
| K, Lb/In | 166.67 |
| Recoil Weight | 167.7 |
| Twist Weight | 242.8 |
| End Weight | 131.6 |
| Tip Weight | 202./6 |
| 9 O'Clock | 94.7 |
| 3 O'Clock | 94.9 |
| Butt End | 144.5 |
| COF, Main | .339 |
| COF, Cross | .300 |
A Hybrid View…Part 2
Let’s Look at a Hybrid Graph
A client asked, ” Would putting natural gut in the cross string instead of the main string create a softer string bed?”
That question is the precursor to the graph below, so I will let the video tell the story.
This graph does not reflect the stiffness of polyester string. So, in any format, a natural gut may help soften the string bed if polyester is used.



Racquet Quest, LLC


