Diadem Project Bublik 98: Specs, Development & What We Know
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Updated 14 August 2026: Diadem's public Project Bublik page still lists the project as Coming Soon. The specification points below are based on current Diadem campaign material already verified by TRE; public pricing, retail availability and a complete final specification sheet are not yet published on the Project Bublik landing page.
Project Bublik is becoming one of the more interesting player-led racket launches of 2026.
When Diadem announced Alexander Bublik's partnership in April 2026, the brand specifically pointed to his feedback on feel, weight and playability and said the team was working with him on the development of a new racket.
The clearest current campaign material identifies the Project Bublik 98 as Bublik's model, with a 98 in² head, a 302 g unstrung weight and a 16x20 string pattern.
This is a first look, not a review. Until the frame is measured and tested on court, confirmed specifications need to stay separate from assumptions about how the racket will actually play.
Project Bublik 98: confirmed details from current Diadem material
| Detail | Project Bublik 98 | Evidence level |
|---|---|---|
| Head size | 98 in² | Confirmed in current Diadem material |
| Weight | 302 g unstrung | Confirmed from current Diadem material and Diadem's unstrung specification convention |
| String pattern | 16x20 | Confirmed in current Diadem material |
| Range position | Smallest head | Confirmed in current Diadem material |
| String-bed position | Tightest 16x20 in the range | Confirmed in current Diadem material |
| Balance position | Most head-light option in the range | Confirmed comparative description; exact balance not stated here |
| Bublik's model | Yes, identified by Diadem as such | Confirmed in current Diadem material |
The 302 g figure is treated here as unstrung. Do not convert that into an assumed strung weight: strings, overgrip, dampener and any customization can materially change the measured frame.
Bublik was part of the development process
This is what makes Project Bublik more interesting than a normal signature cosmetic.
In its 8 April 2026 announcement, Diadem co-founder Evan Specht said Bublik's precision around feel, weight and playability had pushed the development team and described the work as a process of building the racket together.
Diadem's current Project Bublik landing page also quotes Bublik discussing the brand's tools for developing rackets for him.
Diadem's original Bublik announcement and the official Project Bublik page are the primary public sources used for the development story.
The development imagery is worth a closer look
Diadem's campaign photography gives gear-focused readers more to study than the finished paint alone.
In the official development flat lay, multiple tagged iterations are visible around the final black-and-gold frame. The imagery includes tags for Project Bublik Ver.01, Ver.02 and Ver.03, plus a separate Frame Mold Ver.04 tag. Dates visible on several tags point to iterations across late 2025 and early 2026.
That is a visible campaign clue, not a complete engineering history. A photograph does not tell us what changed structurally between each version. What it does show is that Diadem chose to make iteration, shape work, finish selection and player feedback part of the public story.
Why the 98 and 16x20 combination is interesting
A 98 in² head with a 16x20 pattern is a useful technical clue, but not a complete description of how the racket will play.
Compared with a conventional 16x19, an additional cross can contribute to a denser string-bed response. The actual result still depends on spacing, head geometry, beam, layup, stiffness, swingweight and string setup.
So TRE is not calling the Project Bublik 98 a low-launch control frame, a spin frame or a power frame before testing it. The pattern is confirmed; the court response still needs to be measured and felt.
What is still unconfirmed for the final retail frame
As of 14 August, Diadem's public Project Bublik page still says Coming Soon and does not provide a complete final retail specification table. Before making a full technical judgement, TRE still wants verified values for:
- Exact balance measurement
- Swingweight
- Stiffness or RA
- Beam dimensions
- Length
- Construction and material technologies
- Retail price and availability
- Bublik's exact personal match specifications
- His current string and tension setup
Some campaign artwork appears to show additional unlabeled numbers. We are deliberately not assigning meanings to them until Diadem publishes them in a clear specification context.
Retail Project Bublik 98 vs Bublik's personal tour frame
Diadem calling the Project Bublik 98 "Bublik's model" is important. It still does not prove that every retail number is identical to his personal match rackets.
Professional players can customize static weight, balance, swingweight, grip build and other variables. A retail frame can be developed around a player and still be tuned differently for that player's own rackets.
For now, the clean wording is: the Project Bublik 98 is the model Diadem associates with Bublik, while his exact match specification remains a separate question until it is confirmed or measured.
For the broader distinction between retail, pro-stock and player-used claims, read TRE's player-used racket verification guide.
The details make it feel specific to Bublik
The black-and-gold finish is restrained from a distance. Up close, the personal details are more obvious.
Bublik's signature appears in gold on the frame. The more memorable detail is a handwritten line inside the racket:
"Sometimes I hit the yellow ball."
It is a small detail, but it gives the cosmetic a distinct Project Bublik identity rather than reading like a generic signature treatment.
What TRE wants to test when the frame is in hand
The first priority is measured data. Static weight, balance and swingweight will tell us much more about the frame's real positioning than launch language alone.
On court, the useful questions are:
- How stable is the 98 at stock weight?
- What is the natural launch from the 16x20 bed?
- How much spin access does the spacing provide?
- How does the frame respond on flatter contact and touch shots?
- How sensitive is it to string choice and tension?
- How much room is there for customization?
Those are the questions that can turn the launch story into a useful racket review once testing is possible.
First read
Project Bublik already has a stronger development story than a simple signature paintjob because Diadem is showing the player, product and iteration process together.
The current verified starting point is 98 in², 302 g unstrung and 16x20, with Diadem positioning the Project Bublik 98 as Bublik's model within the range.
The remaining work is deliberately practical: get the complete final technical sheet, measure the frame and test it on court. This article will be updated as Diadem publishes the missing retail specifications and TRE has reliable measured data.
What should TRE test first on the Project Bublik 98? Send the question to @tennisracketseu. For a useful comparison, include your current racket, string and tension.