IntoBadmintonFindings drawn from manufacturer specs, community sources (BadmintonCN, Reddit r/badminton, BadmintonCentral, video reviewers), and on-court testing. See our editorial process for the full citation model.
Why brand spec sheets are not enough
Yonex labels shafts Stiff or Extra Stiff. Victor uses similar text labels. Li-Ning uses Hard or Hi-Flex. None of these scales line up between brands — a Yonex Stiff is not the same as a Victor Stiff. This makes cross-brand racket comparison genuinely difficult unless you have all the rackets in your hands at once. Reviewers who want to compare a Yonex Astrox 88D Pro 2024 to a Li-Ning Halbertec 9000 Power need a more rigorous measurement, and that is where the Yuan-style protocol comes in.
What the Yuan-style protocol does
Yuan-style (源式) is a shaft-stiffness measurement protocol that has gained traction on Chinese badminton forums, particularly badmintoncn.com. The protocol applies a standardized force to a clamped shaft and measures the deflection in millimeters. The result is a single number — typically between 6 and 9 — where lower means stiffer. So a shaft at 6.71 (Yonex Astrox 100ZZ) is harder than a shaft at 8.33 (Li-Ning Halbertec 8000). The numbers are reproducible across rackets when measured on the same rig, which is what makes them useful.
The 2024-2026 Yuan-style benchmark table
Here are commonly cited values from BadmintonCN testing, ordered stiffest to softest: Yonex Astrox 100ZZ 6.71, Victor Auraspeed Hayabusa around the same range, Yonex Astrox 99 Pro 2 7.43, Yonex Astrox 88DP New Color 7.59, Li-Ning Halbertec 9000 Power 7.65, Yonex Arcsaber 11 Pro 7.86, Li-Ning Halbertec 9000 7.92, Yonex Astrox 88SP New Color in the 7.5-7.6 range, Li-Ning Halbertec 8000 8.33, Li-Ning Bladex 800 Speed 7.83, Li-Ning Bladex 800 New 8.58. Not every shaft has a published number, but enough of the 2024-2026 flagships do that you can sanity-check a shopping decision.
What the number does and does not tell you
What it tells you: how much active force you need to flex the shaft. Shafts under 7.5 require concentrated, fast power strokes — they reward technique and punish soft swings. Shafts above 8.0 are forgiving for amateur players and recover well from imprecise force. Shafts at 8.5 or higher are sugar-water by design. What it does NOT tell you: how the frame transmits that energy, how the bend point sits, whether the racket is head-heavy or head-light, what the swing weight is, how the sweet spot feels. A stiff shaft in a soft frame can lose power on smash (this is the 卸力 problem reviewers discuss with the Halbertec 9000). A medium shaft in a thick frame can feel quicker than a stiffer shaft in a thin frame.
How to use it when shopping
First, locate yourself on the scale. If you are a recreational or club-tier player, target shafts at 8.0 or higher (Halbertec 8000, Astrox 77 Pro, Nanoflare 700 Pro, Bladex 800 New). If you are competitive (Division 4-2 Irish league, BadmintonCN 5-7, USAB Class B-A), 7.5-8.0 is your sweet spot (Astrox 88S Pro 2024, AxForce 90 New, Halbertec 9000 Power, Bladex 800 Speed). If you are pro-track, sub-7.5 is on the table (Astrox 100ZZ, 100ZZ VA, 88D Pro 2024, Auraspeed HS Plus). Then refine by frame profile, head weight, and play style — but the Yuan number rules out most rackets that will not match your force profile in the first 30 seconds of looking.
Caveats and limits
Yuan-style numbers come from independent testing and are not Yonex, Victor, or Li-Ning official data. The measurement rig and protocol can vary between labs, so a 7.6 from one rig may be a 7.4 on another. Per-batch shaft variance also exists — particularly with Li-Ning, where the BadmintonCN reviewer's weighed 10 Halbertec 9000 Power samples and got swing-weight variance well outside the published spec. Treat Yuan numbers as a useful guide, not a precise truth. They are still the best cross-brand quantitative data available to amateur shoppers.
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