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Browse all 788

Head to head

Gamma IO 17 (1.23) vs Yonex Poly Tour HS 16L (1.25)

IO 17 (1.23) leads on 3 of 6 measurements. The widest gap is ball bite, where Poly Tour HS 16L (1.25) is 41 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Gamma

IO 17 (1.23)

Polyester · 17 ga

Yonex

Poly Tour HS 16L (1.25)

Polyester · 16L ga

Stiffness lower = softer, kinder on the arm
19866th pct
19867th pct
Tension loss lower = stays where you strung it
3048th pct
2944th pct
Energy return higher = livelier, more free power
8957th pct
8848th pct
Spin potential higher = more spin off the string bed
5.774th pct
5.774th pct
Ball bite higher = grabs the ball harder
0.39621st pct
0.46162nd pct
String friction lower = strings slide and snap back
0.0694th pct
0.08126th pct

Bars are percentile against all 788 strings, and the marked side is the one that measures better, which is not always the one you want. A firmer bed is worse for your elbow and better for your control, and no measurement knows which of those you came for.

Which one wins, by problem

Each string's standing on the site's rankings, out of every measured string in the database. This is where a comparison stops being arithmetic and starts being a decision.

Swapping between them: what tension?

Bed stiffness is published at one reference tension, so the only honest conversion is to scale it. These are starting points from 52 lb, not prescriptions. The calculator takes your own tension.

Coming from IO 17 (1.23) at 52 lb

String Poly Tour HS 16L (1.25) at 51.8 lb 23.5 kg

Coming from Poly Tour HS 16L (1.25) at 52 lb

String IO 17 (1.23) at 52.2 lb 23.7 kg

Hybrid: what if you used both?

Estimated, not measured. No hybrid combination has been tested as a bed. These figures are the two strings' own lab measurements weighted by how much of the bed each one actually is. Treat them as a guide to which way a pairing moves, never as lab data.

IO 17 (1.23) mains / Poly Tour HS 16L (1.25) crosses

Stiffness67th pct · 1 measured
Tension loss47th pct · 1 measured
Energy return54th pct · 1 measured
Spin potential74th pct · 1 measured
Ball bite27th pct · 1 measured
String friction8th pct · 1 measured

Poly Tour HS 16L (1.25) mains / IO 17 (1.23) crosses

Stiffness67th pct · 1 measured
Tension loss46th pct · 1 measured
Energy return53rd pct · 1 measured
Spin potential74th pct · 1 measured
Ball bite57th pct · 1 measured
String friction19th pct · 1 measured

Open this in the hybrid builder

Which goes dead first?

Estimated from tension loss, which is the only thing the database measures about ageing. This is when the bed stops playing the way you strung it, not when the string breaks.

IO 17 (1.23)

~26 hours of play

Poly Tour HS 16L (1.25)

~27 hours of play

Both strings in full

Every published measurement
StringGaugePriceStiff lb/inLoss %Power %SpinBite COFFriction COF
Gamma IO 17 (1.23) Polyester17find19830895.70.3960.069
Yonex Poly Tour HS 16L (1.25) Polyester16Lfind19829885.70.4610.081

Add a third string IO 17 (1.23) in full Poly Tour HS 16L (1.25) in full