Shaft Flex
Also known as: flex rating
Shaft flex describes how much a shaft bends during the swing. Ratings run from L (Ladies) through A (Senior), R (Regular), S (Stiff), to X (Extra Stiff) — matched to swing speed for optimal launch.
A shaft that is too stiff for a player's swing speed will not flex enough to boost launch and feel dead; too flexible a shaft overloads at the wrong moment, producing inconsistent timing and shots that go too high or spray laterally. As a rough guide: under 85 mph driver club speed → Regular; 85–95 → Stiff; 95+ → X-Stiff. These are approximations — tempo and transition also matter, which is why custom fitting with a qualified fitter is the most reliable way to find the right flex.
Example
A 70 mph swing speed player fitted into an Extra Stiff shaft produces pushes and misses right because the shaft does not flex and return on time.
Related terms
- Club SpeedClub speed is how fast the clubhead is moving just before impact, in mph. It sets the ceiling for ball speed and distance — but only if contact is clean.
- Driver LoftDriver loft is the angle stamped on the club face — typically 8–12° for tour players, higher for moderate swing speeds. The correct loft maximizes carry by delivering the optimal launch-spin combination.
- Sweet SpotThe sweet spot is the center of percussion on the clubface — the point where a strike produces maximum energy transfer to the ball, felt as minimal vibration and maximum distance.
Related guides & benchmarks
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