Four Terms the Flex Label Never Tells You
None of these can be read off a sticker. Each one comes from putting a shaft's tip section on the rig by itself.
Tip Deflection
How far the terminal section of a shaft bends when a controlled load is applied at the tip alone, isolated from the rest of the profile. Two shafts with identical overall flex ratings can show noticeably different tip deflection numbers — and that difference is what golfers feel as "boardy" or "whippy" at impact.
Taper Ratio
The rate at which a shaft narrows from butt to tip. A steeper taper concentrates stiffness differently than a gradual one, even at the same finished tip diameter, which changes how load builds through the transition and release.
Recovery Time
How quickly the tip section straightens back out after being loaded and released. A shaft that recovers slowly can still be moving when the clubhead reaches the ball; one that recovers too quickly can run out of load before impact and deliver less than its full potential.
The Flex Letter Problem
"Regular," "Stiff," and "X-Stiff" describe a shaft's average resistance to bending across its whole length — not the tip section specifically, and not consistently between manufacturers. A "Stiff" from one shaft line can carry a softer tip than a "Regular" from another. The letter is a starting point at best.
Whole-Shaft Frequency vs. a Tip-Only Reading
Whole-shaft frequency — the cycles-per-minute reading you get from clamping a shaft at the butt and setting it oscillating — is a useful number, but it's an average across the entire length. It can mask a soft tip on an otherwise stiff shaft, or a stiff tip on an otherwise moderate one.
Our rig clamps closer to the tip and applies load there specifically, so the reading isolates the section that governs delivered loft and kick timing instead of blending it into a single full-length number.
Want the Longer Explanations?
Off-Season Notes covers each of these terms in more depth, or bring your questions straight to a session and we'll walk you through your own printout.