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Browse all 791

Head to head

Tecnifibre Black Code 4S 18 (1.20) vs Yonex Poly Tour Spin 16L (1.25)

They split the measurements 3–3. The widest gap is string friction, where Black Code 4S 18 (1.20) is 24 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Tecnifibre

Black Code 4S 18 (1.20)

Polyester · 18 ga

Yonex

Poly Tour Spin 16L (1.25)

Polyester · 16L ga

Stiffness lower = softer, kinder on the arm
21079th pct
21482nd pct
Tension loss lower = stays where you strung it
2537th pct
2741st pct
Energy return higher = livelier, more free power
8850th pct
8952nd pct
Spin potential higher = more spin off the string bed
6.180th pct
6.383rd pct
Ball bite higher = grabs the ball harder
0.53287th pct
0.63298th pct
String friction lower = strings slide and snap back
0.08739th pct
0.10063rd pct

Bars are percentile against all 791 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 Black Code 4S 18 (1.20) at 52 lb

String Poly Tour Spin 16L (1.25) at 51.2 lb 23.2 kg

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

String Black Code 4S 18 (1.20) at 52.8 lb 23.9 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.

Black Code 4S 18 (1.20) mains / Poly Tour Spin 16L (1.25) crosses

Stiffness80th pct · 1 measured
Tension loss38th pct · 1 measured
Energy return51st pct · 1 measured
Spin potential81st pct · 1 measured
Ball bite90th pct · 1 measured
String friction48th pct · 1 measured

Poly Tour Spin 16L (1.25) mains / Black Code 4S 18 (1.20) crosses

Stiffness81st pct · 1 measured
Tension loss39th pct · 1 measured
Energy return51st pct · 1 measured
Spin potential83rd pct · 1 measured
Ball bite97th pct · 1 measured
String friction57th 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.

Black Code 4S 18 (1.20)

~29 hours of play

Poly Tour Spin 16L (1.25)

~28 hours of play

Both strings in full

Every published measurement
StringGaugePriceStiff lb/inLoss %Power %SpinBite COFFriction COF
Tecnifibre Black Code 4S 18 (1.20) Polyester18$11.9621025886.10.5320.087
Yonex Poly Tour Spin 16L (1.25) Polyester16Lfind21427896.30.6320.100

Add a third string Black Code 4S 18 (1.20) in full Poly Tour Spin 16L (1.25) in full